Well done, what a great walk!
My limit is about 7 to 9 miles a day, then my feet and knees dance their own dance.
Once I did more then 30 caches a day (it was a series of 50 or so) and stopped not because of injuries but of loosing the interest in finding just another boring Micro under another boring park bench only to get +1.
Hope to do a 100-cache-series along a 100km-bicycle-path at Pentecost together with my family. This is connecting fun and (caching) business...
friedelfindus
(temporarily as a guest cacher in the East Midlands)