To find this cache, you must first find these three mighty weapons:
All the guns are next to a road somewhere within 200 kilometers of the posted coordinates of this cache. The posted coordinates are the average of the coordinates of the guns (latitude is the average of the three latitudes and the longitude is the average of the three longitudes), so when you have found any two of the guns, you can calculate the coordinates of the third one.
At each gun observe the direction the gun points to and round the result to the nearest whole degree from true north. Then determine where you would be if you started form the posted coordinates and moved first 3507 meters to gun #1 direction, then 1278 meters to gun #2 direction and finally 1102 meters to gun #3 direction. Go there and you'll be standing where I stood while shooting the picture on the left. Now go in and look to the right, you'll see the cache.
The terrain rating is based on the M&Ms system. The site is more than 10 kilometers from tarmac and you may want to use a four wheel drive vehicle, although a 2WD can do it too. I used an Opel Astra when I placed the cache. There is some climbing involved after you leave the vehicle, but not too extreme. The Clayjar system would rate the terrain four stars. The climb is easiest if you approach roughly form the direction you would be using if you had actually followed the three leg path described above.
The difficulty rating reflects the mystery. The cache itself is in plain sight when you get close enough.
There is an awesome view from the cache site, but please don't post pictures of it on your log entry as they would reveal the location and spoil the mystery.
To get the most accurate results for the final coordinates you should calculate the three legs along great circles starting with the required direction. Not rhumb lines. Use WGS-84 ellipsoid model. Some GPSr units can do this calculation for you, but they might use somewhat inaccurate algorithms like for example my Garmin unit that gives a result more than ten meters off.
I got a report that gun #3 is not there any more. I'll try to come up with a replacement, but until then you'll have to find the old gun virtually. There are sites in the Internet that offer aerial or satellite photography of the area. You must find a photo of gun #3 as it was and determine it's direction from the photo. To make the task easier, I give an additional hint that the direction is nine degrees off some cardinal direction.
Gun #2 has apparently been moved upwards but its horizontal location hasn't changed and the direction it points to matches the original direction accurately enough that if its whole degree rounding doesn't match the original exactly, it at least matches it well enough that it can be made exact using the information in the encrypted hint.