The Rabati is a 9th-century fortress that towers over Akhaltsikhe from a ridge above the town. It was extensively restored between 2011 and 2012 — perhaps too extensively; the reconstruction is clean-cut and polished in a way that feels more theatrical than historic, but the site's structure is genuine and the views from the ramparts are excellent.
Inside the walls, the complex contains the Samtskhe-Javakheti History Museum (in the restored palace building), a 13th-century Georgian Orthodox church, a mosque dating from the Ottoman period, and the remains of a madrasa. The coexistence of these religious buildings within a single fortress enclosure reflects the city's layered history as a Georgian, Ottoman, and then Russian city over seven centuries.
Entry to the outer fortress grounds is free; the museum and some inner buildings have a modest entrance fee. The climb from the old town to the fortress gate takes about 15 minutes on foot. A restaurant inside the complex has a terrace with views over the valley.