SparrowHawk,
You are exactly right. Nothing against the Indian people. But, it would be plundered immediately. Not because they are thieves (quite the contrary). But because 90% of the people are dirt poor and see something of value left apparently discarded. And, the shear density of people is hard for westerners to comprehend. There simply is no location (that I have found) where a hide would go undetected. And, if I did hide it that well, there would be a lot of DNFs.
I don’t want to see any DNFs posted for this cache. I know what it is like to get to someplace exotic and only have a few hours to devote to geocaching. Coming up empty handed is very disappointing.
I like the huge concrete safe idea. Close to an idea I have been hatching. If I find a construction sight with a willing foreman (a few Rupees helps), I might get the metal box encased in a bridge abutment or building. Now that’s permanent! The door could be disguised as an electrical panel with a big lock.
Perhaps I combine this with your idea. The construction sight I was thinking of could be great cover for building the concrete monolith you describe. The needed materials and strong backs could be siphoned off of the construction work (for a few Rupees).
CacheNCarryMA
Close to another thought I had. I was thinking of using the grounds of a Western hotel which usually means protected by security. But, the notion of having to find a specific shop in a bizarre is far more on the spirit of Geocaching adventure. How about the arrangement is that geocacher has to pay the sum of 50 Rupees (about a buck) to the shop owner for the box on the shelf with the Geocache label on it. That creates ongoing incentive to the shop owner. A box he can sell and keeps being put back on the shelf. Wonder if that would fly with the reviewer? Considering the difficulty of caches in India, they might give me a little latitude.