The Akhtala monastery was a long time not serviced but just recently activated again. It is part of the Akhtala fortress and is situated on a big rocky cliff about 5km away from the main road between Yerevan and Tbilisi. The whole complex dates back to the 10th century, compared to all other armenian monasterys it distinguishes from its precious and unique frescos which are very well preserved and in original condition.
More information you find in the wikipedia article or you just ask Pater Vigen. He speaks english very well and likes to give you some details about the monastery complex and the frescos. Also there is a woman, that sells postcards and other stuff in the monastery, she speaks some german. Furthermore she owns the little grocery shop outside the monastery, so if you find the doors closed just ask her, she has the keys.
To get the cache you first have to find A,B,C,D,E,F,G.H:
When you enter the complex through the gate you´ll find a sculpture consisting of two big rings. Pater Vigen said, if couples go through they will leave all the bad things (the snake and scorpion) behind and are facing a good future (towards the monastery). The year the sculpture was created is AXXB.
Before approaching the monastery, take a look at the remains of the little church on the right. Closeby the entrance you will find some stone with a 3-digit number on it CDE (C+D+E=10). It is probably part of the monasterys spire which collapsed long time ago. Inside the monastery is a sketch that shows how it used to look like, the original height was twice of the remains today.
Now go into the monastery and enjoy the beautiful frescos.
When you stand in front of the altar, turn to your left and have a closer look on the frescos at the left aisle: Somewhere you will find a bird sitting on somebodys head. How many people F (F is uneven: F=2n+1, n=0,1,2,3,4...) do you count in this painted scene?
After this turn around that you face the right aisle of the monastery. The persons in the lower row seem to be saints due to the shining halos around their heads. The number of saints/halos take as G.
Now go back towards the entrance, above the left side of the door there is a fresco with three big boxes, probably coffins. How many people H are inside these altogehter?
In case you find the door locked with nobody there to open it, you can alternatively receive F, G and H on this way:
Go around the monastery and look on the walls for the engraved letters B.H. You will find them closeby a little window. Next to the B.H. is a year date engraved which you take as WXYZ (W+X+Y+Z=20).
PS: be aware of snakes on the monastery grounds (where you will find the cache)! Nevertheless we camped there right at the end of the cliff with a nice view, Pater Vigen had the Idea. As there is no well nearby, bring your drinking water or buy it in the shop.