I loved the virtual tour to solve this one. A few numbers I wasn't too sure about, so I cross-referenced them with the historic tour and thought I was all set. The numbers led me to somewhere very promising and I gave it a good search but didn't find nuthin.
Returning home, I looked at the puzzle again to see if I hadn't goofed a number or two and sure enough...it looks like I was off on one number. It's still in the same general area but a spot further along that I didn't check. So, I'll return and give it another go.
Thanks for the history lesson, s|s. When I first saw the statues, I figured someone would make use of them to create a cache.