About 40km from Sochi, this chain of caves is a popular and worthwhile excursion. Some 12km of the cave system is mapped, but tourists have access to 500m of illuminated passages. Some of the rooms are quite spectacular, decorated with stalactites and stalagmites. The largest 'hall' is named after Prometheus, the Greek deity who was chained to nearby Mt Fisht as punishment for sharing fire with humankind.
There's no public transportation to Vorontsova, but you can hire a taxi (about R3000) or join a tour (R700). It gets cold inside, so dress accordingly.