Kakavaberd is a ruined Armenian fortress set in the rugged country beyond Garni, above the Azat River landscape and near the Khosrov reserve. Its walls are fragmentary, but the position explains everything: this was a lookout and refuge built for a hard, broken terrain.
Reaching it is more of an excursion than a casual stop, often involving rough roads or a hike depending on conditions. Go for the combination of ruins, cliffs, and empty space, and avoid treating it like a quick add-on after the Temple of Garni.