Khertvisi Castle guards the meeting of the Mtkvari and Paravani rivers, a strategic position that explains the fortress before any signboard does. Its walls and towers rise from a rocky spur on the approach to Vardzia, making it one of the most natural stops in the valley.
The castle is partly ruin and partly viewpoint. Climb for the river geometry, the defensive logic, and the sense of how many layers of Georgian history passed through this corridor before the cave monastery became the headline.