Narikala Fortress looms over the old town from a ridge between the sulphur bath district and the Mtkvari river gorge. Parts of the fortress date to the 4th century, and it expanded continuously through the Arab, Persian, and Georgian periods. The view from the upper walls takes in the whole sweep of the old city — the domed bathhouses, the medieval churches, the river, and the modern city spreading beyond.
Getting up there is easy: take the cable car from Rike Park (across the river) or walk up through the old town lanes. The small Church of St Nicholas inside the walls was restored in the 1990s. There is no entry fee. Allow an hour to walk the circuit of the walls and take in the views. Go at sunset if you can — the light on the old town below is exceptional.