Castellana Grotte is on the Ferrovie del Sud Est (FSE) line between Bari and Taranto, with frequent services throughout the day. From Bari it takes about 45 minutes; from Taranto roughly an hour. The station is about 15 minutes on foot from the cave entrance — the route is signposted.
By car, Castellana is about 40 kilometres southeast of Bari via the SS100, a straightforward drive on good roads. Parking is available near the cave entrance.