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Greetings, professionals.

I am not a professional, but have recently found that I need to buy some equipment to help with my benchmark hunting (I want to beat down my NOT FOUND ratio, and feel a little more like an NGS volunteer with tools).


I have a hand trowel for minor digging purposes, as I got tired of using whatever crushed soda can was available to dig down to a station.


I of course have my clipboard with printed DATASHEETS, and dorky National Map volunteer badge. I think I found it in a box of Wheaties.


I think I need a roleable tape measure, as my toolbox tape measure only goes to 30'. What would you recommend, for a reasonable price, that's long enough, and where could I reasonably expect to get it?


I'm thinking about getting an orange safety jacket, but worry that might make me invisible, rather than noticed.



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Here is something that works well. I would get the 165 ft version in 10ths and 100ths of foot, not inches - surveyors do not measure in inches.




Also I use these to tie one end of tape down so I can measure by myself but you can make something for that out of rigid metal wire.




You might find these items cheaper by shopping around but I find this company handles quality items and delivers fast. Forestry Suppliers


You also need one of these



Edited by elcamino
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Take a look at the posts that Black Dog listed. There are a lot of good suggestions there.


My tape LOOKS like Elcamino's but is a 100' cheapie from Lowe's. It doesn't measure in tenths of an inch or meters but it gets the job done if I have done my meter-feet conversion right. I don't need 10ths of an inch to find a foot square block of concrete... usually. 100' is a bit too short for some triangulation station measurements and I would love to have meters, but I am happy with what I have.


I like Elcamino's stakes! But since I didn't have a source for forestry stakes I grabbed some spikes--huge nails--also at Lowe's, and sprayed them orange so I can find them.


For a shovel I bought a folding camp shovel--the smallest I could find. I am on my second one and about to get my third because $10 shovels are about as good as one would think a $10 shovel would be, and I tend to use them hard. Still, it folds up and is easy to carry.


To keep all my stuff in I swiped my daughter's school backpack. Yeah, I had to buy her a new one, but I would rather SHE have the nice one and I take the worn one. I throw all my stuff in there and walk to where I need to go, hands free if I need to climb an embankment or walk a mile.


Finally, based on a suggestion in one of those posted threads, I never go anywhere without my "probe", which is a Walmart camp fork with the fork part snapped off, leaving me with a wooden handle on a metal stick. Again, they don't last forever--one unexpected probe into an underground rock and you will have a bent probe. I unbend em and keep going until they start bending too easily. Then I get a new one for less than $5. It is the only thing I can't get in the backpack but serves as an impromptu bushwacking tool at times (leading to more bends in it).


Don't have the truck. Could use one from time to time though. See my post for KW3127 for a time I would have been happy to have 4-wheel drive. Overall I like having my Ford Focus because it is pretty narrow and has allowed me to squeeze off the road onto the shoulder in places where a larger car or truck wouldn't have fit.

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Also it helps at times to have a traffic cone to place on the mark so its location shows in the photos like in the one below. I was driving down the hwy one day and found one laying in the middle of the road. Fell off telephone company truck and now rides in my truck.



Edited by elcamino
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No offense Elcamino, but THAT is something I don't plan on carrying in my Ford! I have enough junk floating around in it.

I forgot to mention that I have USGS 1:24000 scale maps for about 25 miles around my area, each marked with benchmark names. I find the topo maps very useful in determining exact location of the marks.

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I have the Delorme Topo quads on my Dell Notebook along with the street atlas.


I made a file with all the control points in it, one with Horizontal and one with Vertical, then load them up in either program, plug my Gramin (with remote antenna on roof) into the notebook and drive to the area of the mark on the map. Makes finding marks easy when roads etc have changed. This is how I did it at work, state would not let us have TopoQuads so I spent my own $$ on them and had to take if off the notebook when I left. It saved me countless hours


Here is a small sample of that horizontal control point file for my area;



Edited by elcamino
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Pruning snips.


Around here we have those awful briars, and half the time the one plant as far as the eye can see is right on top of the benchmark. Huge help.


I also think a full size shovel is nice. Helps move those briars from a distance, and we've found a couple here on culverts where there was some heavy dirt and gravel on the top of them. Real digging was required.

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I've used my Leica LRF800 laser rangefinder while looking for benchmarks. It beats trying to run a tape measure across grass, boulders and puddles, or to the middle of a busy roadway. I may also need to use it while placing a cache in an area with really bad GPS reception. Its advertised accuracy is +/- one meter, with an approx. maximum range of 800m depending on the target.


(I had the rangefinder aleady, I didn't buy it with benchmark hunting in mind.)

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Not to be a killjoy, But, elcamino, aka Z15 had it right and had it best. A tape measure and some chaining pins, or something that will work as a chaining pin such as a super cheap screwdriver stabbed into the ground is really the most accurate. If you like whiz bang, the Lasers and such are fun, but there are way too many times that the accuracy can get called into question because of the many things that can affect it. I guess I would have to say that they make a better indoor tool than outdoor in many instances. You may certainly do as you like but if a laser and a tape were to cost the same money. I'd buy the tape.


Low tech solutions to problems really are the best option. Batteries never die, no computer to become a weak point in the process. Don't usually fail when wet or dropped. Running a tape across anything is not that difficult with the right tools and techniques.


For measuring from the centerline of many average roads when you are alone, take your 25 foot self retracting tape and measure out to the edge of pavement, curb or sidewalk from the center, and stick your chaining pin or screwdriver in the dirt or grass, what have you at some amount of whole feet, then switch to your 100 foot tape, pull the pin, slip it through the end of your tape and walk in the direction you are measuring. Repeat this as many times as you need to pull your measurement. remember to pull the tape taught when reading your hard number. Add the number you pulled first from the centerline of road to the edge to what you pulled on the big tape. This method will help you get from the hard to the soft surface in most cases.


When working alone, If you are on a wider hard surface than you can get to the edge of in 25 feet, use chalk and stay on the retractable. It is faster, safer and easier to handle. besides, you don't ever want a car to drive over your 100 foot tape.


Now most measurements you need are not too long but you get the idea. 3 screwdrivers or chaining pins are minimum as you will be leapfrogging these and you will need to leave 2 in the ground to reference you to the straight line you are attempting to measure. Chaining pins are red and white to aid in finding them but can be hard to see at 200 feet, screwdrivers not any particular color yet at 200 feet are no different. Those little landscaping wire flags will help you find them. The wire flags also help you keep track of other points if needed so having a half dozen or so will not be a bad thing. Remember, we are often measuring from more than one point on the "to find", and if it doesn't work like we thought, if we did leave a flag, we can then double check ourselves.


When we reel up the tape, I recommend wiping the reel tape with a rag to catch the dirt and grit that will be on it from laying on the ground, even in dry weather. If you do not take a shop rag or even a paper towel and do this every time, try to remember to do it when you get home or back at the car before you stow it, as leaving the tape soiled and or wet is very bad for the long term survival of them. On the retractables, wet days are tough on them too and grit on the blade will cause them to bind when retracting. At the end of the day they will need wiped dry or you will have a rusty unreadable tape next time. A nice treat for these tapes is a rag with a little WD-40 sprayed on when you retract them to displace the moisture and safeguard the tape, but only at the last wipe down, and don't use too much. Fresh WD-40 loves to attract dirt. The first use of the retractable next time may be advisable to be a re wipedown and inspection so to dry off the remaining oil, and make sure things are all happy.


Getting back to Lasers. When Surveyors use Lasers, or what we call EDM, which is usually built into a Total Station. We measure between the instrument and a Prism, or reflector we place in the field and a distance above the ground... The big deal is that a clear view is desired to the prism. With the consumer device, you will likely be measuring without the prism, and near some surface which can clutter and confuse the measurement. The problem is that from where you are standing, you may think you are measuring a distance but some clutter could be being read at 5 feet closer or further and so it throws you off. The From where you are standing situation compounds itself because it could be 5 or 10 feet of error from the clutter but it looks right from the 85 or 120 feet away that you are measuring. You think it looks right and so you never realize the error slipped in.


Those who like these things are welcome to keep using them but I just wanted to point out the weaknesses, and for the money, the cheap ones are far worse than the spendy, yet the spendy are susceptible as well. It is well worth considering before you lay your money down.


One more alternative is to buy a measuring wheel. I have used them many times and they are great for getting in the ball park when close estimates are all you need... they are only accurate to the whole foot and of course that can get shaky the further you get from where you started but if you need to find an azimuth mark which is .55 miles away as the road or trail travels, calculating that into feet and walking the wheel is not a bad walk. You will look just lie all the other people who seem to have a reason to be there and maybe even strike up a conversation. It happens! Price is about $70, and you will likely use it over and over if you are serious at this hobby. Further as an ease of use deal, you can always see if you can find the station with the measuring wheel and flags before you resort to the tape measures. Go to the tapes if you have no luck with the wheel. It will help keep you clean dry and off your knees and that is often a good thing. The Wheel folds and fits in the trunk. Get the one with the wheel that is around a foot in diameter. Smaller wheels just won't cut it outdoors.



Edited by evenfall
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I use two different measuring items.


A hundred foot steel tape in a closed reel. I have one of the fabic open-reel tapes exactly like the one ddnutzy had pictured, but I like the closed-reel one because it will fit in a pocket or my small pack. To anchor the tape, I use a piece of stiff but malleable wire that I found somewhere that I use for probing. The wire lives in my pack, bent in a V shape for storage. For probing, I re-bend it into an L shape so that it has a handle.


The other mearuring item is one of those fold-up carpenter's rulers that is 6 feet long, but folds to 1 foot long. It is excellent for short measurements because, being stiff, it doesn't have to be anchored. Again, this one is old, and is made of some type of metal instead of the usual wood. The wood ones are fine too, but when extended all the way, you have to be a bit careful or you will break it.

Edited by Black Dog Trackers
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Here is a picture of the tools that I use minius the 15 inch lineup pin that I use as a probe and my food supply since most of the bm's that I look for don't have a McDonalds close by. (image edited out by Red Cedars)

Wow. That's dedication. For me, most of the benchmarks I've found using only good directions.


This brings up another question, though. To what extent is it reasonable to go in search of a benchmark? I mean, my most recent search netted a station mark and one of two reference marks. I didn't go after the second RM because it would have meant hacking down blackberry vines. Now this particular mark was on a utility right-of-way so there probably wouldn't have been much to worry about, but what if it were burried in a state park or some such? How much digging is reasonable? Do you dig for every rock you find with your probe? Do you hack down vegetation to clear a path to your quarry? I'm thinking a machete might be handy for such a situation as I described above, but what limits do we place upon ourselves?


Case in point. SY4909 is within 25 feet of my route to work. Do I show up at the Kingston Ferry landing some Saturday moring with my chainsaw (re: the 1982 finding) and have at it?



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A quick look at the aerial photographs show this area as being a parking lot for the Washington State Ferry slip. I am guessing the 1982 problem of too much brush has gone away, and that the 1994 "Not found" may be more likely.


To speak more to your original question though, the answer lies with the individual. Would I have hacked through the blackberries? Probably, if I had the tool(s) and the time, and thought I would be successful. Others will probably give you varying answers, including what you did, which was walk away. I have hacked my way through some decent brush, and dug as deep as a foot to find a mark.


As for bringing a chain saw, that might be a bit much, but if I suspected station KING was there I would have attempted some way in to locate it. Remember that we do not have to "occupy" these stations like surveyors do--they have to set up their equipment on top of them in order to take readings. We just have to get a good look at the disks. And having said that, if I was able to recover a station such as KING but it was in deep brush, I would make a note of that in my recovery to the NGS so that a following surveyor could make his or her own decision on whether the station was occupiable or worth the effort to use.


Benchmark hunting is up to the individual, and there are as many methods as there are people doing it. It is up to you how you want to pursue it.



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A quick look at the aerial photographs show this area as being a parking lot for the Washington State Ferry slip. I am guessing the 1982 problem of too much brush has gone away, and that the 1994 "Not found" may be more likely.


To speak more to  your original question though, the answer lies with the individual. Would I have hacked through the blackberries? Probably, if I had the tool(s) and the time, and thought I would be successful.


. . .


Benchmark hunting is up to the individual, and there are as many methods as there are people doing it. It is up to you how you want to pursue it.

Actually, the ferry slip has been there a lot longer than 1982, so I suspect that "KING" is probably closer to the water, buried under beach logs. I guess I'll just have to take out the GPS for a closer look. :lol: I'll let you know.


But again to the original question, thanks for your answer. It's pretty much as I figured. Personally, I think my ambition for Benchmark Recovery ends with a machete. If I have to dig for it, I'm more than likely going to walk away. There's just too much of the "Leave no trace" backpacker in me to go beyond that. The blackberry vines are non-native and are considered "Noxious and invasive" by the local agricultural community, so I've no qualms about hacking them out.


Now I've got to go back with a machete to SY3487 to find RM 2 and get a picture. :D


Thanks for the input,

Red Cedars

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Red Cedars and all,


Regarding SY4909, Station KING. There are some cool things going on with this Station.


Try using the GPS, Set to NAD83 Datum, D.M.S (Degrees Minutes Seconds Mode). This from the datasheet: NAD 83(1991)- 47 47 49.30458(N) 122 29 45.46719(W) ADJUSTED will likely appear as 47 47 49.30(N) 122 29 45.47(W) on the GPS, and if you "fly in" a waypoint for that coordinate prior to Hunting, you can use the go to function on the GPS to help find it if it has one. You may be within 5 to 10 feet of it's actual location with a good constellation and WAAS lock when the numbers match. I have also found pushing the Map resolution to the highest resolution will help you see where the numbers click over. This sort of helps you see a window of a sort of higher resolution if you understand the space between the number trips. This helps define the edges of the circle of accuracy you are getting. You could flag the areas where the numbers toggle over to establish the area it should be within.


This is a Second Order Station which made it relatively important, and so the reference marks that go with it should help to locate it today. Here are the bearings and distances to the RM's


SY4909| CF6823 KING RM 12.670 METERS 05245 |

SY4909| CF6825 KING RM 2 50.057 METERS 22413 |

SY4909| CF6826 KING RM 3 62.390 METERS 22413 |


This is a cool example from the narrative, 1962 recovery which I thought many of us will enjoy




Here is an example of how the underground mark was (theoretically) used to re-establish this station when the original was found to be lost. But in this case they feel they found the surface mark in place, only buried with three feet of material. So, they stacked a third monument. This is possibly a triple stacked Station. This is the Why of the underground marks existence back when that methodology was in effect. This one actually was a surface mark that wound up treated as an underground mark and had to be the place marker!


Also, in case you may not know, the RM's usually have Arrows that should point to the Station Mark and that may help. I am still a big fan of the Tape measure and it looks like you have some objects in the area that may help if they still exist.


There is one more issue I would consider on this one Red. Homeland Security has the WSP patrolling the Ferry Lines with Dogs and all as you know, so there is always a State Cop at hand. You may be finding yourself in a sensitive place if you go near the water at a Ferry Landing these days, as this is an area they may not expect to find the Public. It also shares the title as one of the 2 biggest runs the Washington State Ferry System has so keep this in mind while you hunt this Station. Ferry Security has been in the news a lot as you know. I would not like to read about a Geocacher mistaken as a possible terrorist. I was on this Ferry myself a few months back, but it was dark as I headed towards Edmonds. I cannot remember the area where this mark would be located really well.


I would definitely take the Real NGS Datasheet from the NGS website on this one as proof of what I am doing, Which is of course a Volunteer Hunting the Current Status of Survey Markers for the National Geodetic Survey, if asked! :-)


Good hunting,



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Red Cedars,

Here is a little more research, courtesy of USAPhotoMaps (again). I found they have meter resolution photos of urban areas and this was one (an urban area I mean). Take a look at KING Aerial photo.

I wasn't clear on what I though I found on the photo before: it was actually looking at both the aerial photo AND the topo that I determined that the area might have been developed. The topo has a simple road out to some piles for the ferry slip; the photo shows a parking area with staging for cars and a more elaborate slip replacing the old one. It was actually the DIFFERENCE in the two that led me to believe that KING might be gone, or no longer in bushes.

The photo on the benchmark's page shows the location of the station to be in the middle of the parking area. It is possible it has been preserved, but it looks like it is where a car is parked.


A side note about the Washington State Ferry system--the company I work for is doing the new ticketing system for it. Look for it in 2006 if I remember correctly.

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Red Cedars,

Here is a little more research, courtesy of USAPhotoMaps (again). I found they have meter resolution photos of urban areas and this was one (an urban area I mean). Take a look at KING Aerial photo.

Wow, thanks everyone, for the insights. Evenfall, I may try and look for those RMs.


Mloser, I'm assuming that red dot is where the mark is supposed to be by your calculations? Not at all where I expected. I'm sure that ferry parking lot predates 1982. (Okay, I'm NOT sure, but find it VERY difficult to believe otherwise.) They did some remodling of the buildings within the last decade or so, but that lot has been there, like, forever.


I promise this much at least. I will place my eTrex on the place where that dot is, let the sats settle and take a digital picture. I'll post the results here. That much should at least be interesting. :o


In any case, and to at least pass a nod at the thread topic, I won't be taking my chainsaw with me. :o




edited to add: Oh, and I commute via the ferry system. I'm not quite on a first name basis with the WSP officers and their dogs, but close. But your precautions are quite reasonable, so I will do as suggested. Besides, having the sheet will come in handy. And there's a micro-cache right by the parking area as well.

Edited by Red_Cedars
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The red dot is where USAPhotoMaps says the station should be, based on the coords I entered. If I entered them wrong then it won't be there, and that is always a possibility.


I looked at the photo some more and would say, without being there, that it is quite possible that the parking lot has been there since before 1982. I am willing to bet there was SOME sort of parking area in 1982 but maybe it has been enlarged or modernized. I can see that a lot HAS changed since the topo map was last updated, but that appears to have been in 1973, and perhaps updated photogrametrically in 1991, so it is somewhat out of date. One thing that strikes me as odd is that there is an X marking the station on the topo map, but the coordinates put the station to the east of where the map shows it. I usually count on the map to show the mark in relation to nearby references such as roads, buildings etc, and in the case of an adjusted mark like KING I trust the coordinates, so I don't know WHAT to think here.


Also, I don't think that is a car where the red dot is any more, but don't know what to make of it. Maybe it is some sort of equipment or storage box, and the mark is preserved beside it.


The best thing to do is what you said--take your GPSr out and find the coords. You should get a good reading in such a clear area and that will give you a decent indication about where the mark is located.


Good luck on your hunt. All of us "armchair" hunters are waiting to see what you manage to find out.



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I usually count on the map to show the mark in relation to nearby references such as roads, buildings etc, and in the case of an adjusted mark like KING I trust the coordinates, so I don't know WHAT to think here.

Ordinarily I'd be inclined to agree, but check out the find I made this morning:




The coordinates as listed show the mark south and east of HWY 99. I tried to find this yesterday using coordinates only. No luck. I went back this morning with the GPSr in my pocket and used the description. Drove right to it, got out, took some pictures and a new GPSr reading. The description says "Coordinates may not be exact." I'll say. By my GPSr, they're off by 200 feet.


Given that margin of error on KING (which also say the "Coordinates may not be exact"), the mark could very well be at the base of the only 20 to 25 foot bluff in the area, buried under the only logs in the area. I'm learning that while the GPS system is a wonderful tool, it's not much good if the original description isn't based on the same data.


The structure you see next to the dot in the picture is a building with restrooms. People are going to worry when I take my picture later this weekend. Your dot is on the side of the Ladies Room. :D



Edited by Red_Cedars
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As a triangulation station KING is used for horizontal control, so the coords should be precise to the margin of error your GPSr gives you.


SY0045 is used for vertical control and its coords are scaled by measuring off the topo map.


You can see this more clearly if you click on "view original datasheet" and look at the coordinates there--the horizontal control disks are measured down to 5 decimal places, the vertical control disks are to 0 decimal places. The statement on Geocaching that the mark is scaled and adjusted comes from finding the words "scaled" and "adjusted" somewhere in the description. In both cases the confusing wording comes from the NAVD 88 line which is below the NAD 83 line. I will let Evenfall explain how NAD 83 and NAVD 88 relate and differ if he wants, but you can rely on the NAD 83 line for your info. The scaled marks can be off by as much as 600 feet.


SY0045: NAD 83(1986)- 47 52 46. (N) 122 16 02. (W) SCALED


SY4909: NAD 83(1991)- 47 47 49.30458(N) 122 29 45.46719(W) ADJUSTED


One thing you may want to do before hunting is look at topo maps of the marks you are hunting. While the scaled coordinates may put them on the south side of the highway, but the MAP will show them on the north side. I would put 100 percent confidence in the mark being on the NORTH side at this point.


A couple of key things:


1. Use the original NGS datasheet, from the actual NGS site NGS site. The sheets on Geocaching are a few years old and newer recoveries may have been submitted, adding to the information on the sheet. Find a bookmarklet for looking up single benchmarks at Zhanna's cool site.


2. For scaled marks, use your GPSr to get you NEAR the mark, but rely on the description and any research or maps you may have. I rely heavily on topo maps and have about 20 of them for my area, all folded in a box in my car ready to be used, with the NGS datasheets tucked inside each map.


3. For adjusted marks you can rely on your GPSr more heavily, but you will still probably need the description to find the mark, and will DEFINITELY need it to find the reference mark(s).

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You said it well Matt,


NAVD 88 is a Vertical Datum, NAD 83 is a Horizontal Datum. A GPSr is not concerned with Vertical datum. It will only help us locate things Horizontally. I have a GPS Elevation capability on my eTrex Vista, But I consider it a ball park estimate at best. In fact, I rarely even look at that feature. It is a nearly hidden nested menu as it is.


Generally speaking, Our mental note to ourselves is just that when we see that the Horizontal NAD 83 Control has been SCALED, We automatically check to verify if the Station's primary purpose is for Vertical control. It tells us we are dealing with a Bench Mark, Not a Triangulation Station or some other control. That is all. Then we can see if we can improve upon the scaled location with our GPSr.


The aforementioned thinking is sound in most cases, but there are exceptions such as stations which have been given both kinds of control via GPS in the modern day, or Both kinds of control via Optical methods and leveling. I have also seen Old Tri Stations which were given only a vertical update Via GPS, and the opposite holds that some Bench Marks have been given Horizontal Control as well.


This is the case I make, It is fine if all we want is to use the basic information that the Geocaching pages give us, but we can know more, much more if we use the datasheet. Of course Geocaching makes their older copy of that available and much of what we will want will be on it, but the best data is always a comparison of the NGS Datasheet and the Geocaching site to see if anyone else has found it.


Time is a funny thing that plays on Data...


There are 2 marks at a beach front park in Seattle that have been recovered by geocachers. A recent City Parks Sponsored remodel of buildings in this park took out a Station disc which had been in a sidewalk, and a flagpole which had been near the remodeled Building. Both were Third order horizontal and one was a landmark. I have them as not founds. But there was a geocacher find on them. Now, no one else will ever recover them either, and I have updated this at NGS. I could have the Flagpole destroyed in the NGS Database, and am considering doing that, but the Station Disc which is now gone will be eternally not found. It was excavated when the old sidewalk was broken off and hauled off. Depending on how you approach these 2 stations in the future, and depending on what I do in the end, a person may have to look at both Geocaching and NGS to know the full history. NGS will never tell you how many Geocachers did find these before they were lost, but Geocaching will never show the removal of the destroyed Landmark.


It seems to be a good practice to look it all over, but the best, most up to date source for meaningful info is the NGS Datasheet.


Oh, And Zhanna's Site is Cool!


Good luck!



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My GPSr has an electronic compass in it, which is usually good enough to tell which side of the road a mark is on. It is a little tempermental though, and can get misaligned. I've taken to carrying an inexpensive plastic Brunton Sportsman which is adjusted for declination and has sighting aids. It is accurate to about 2 degrees, but I don't recall ever needing that accuracy.

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