A car is essential for seeing El Bierzo properly. The villages, monasteries, and wineries are spread across a wide valley with limited public transport between them. Local buses run from Ponferrada to Villafranca and Cacabelos but services are infrequent and few continue to Las Médulas or up to O Cebreiro.
Cycling is a fine alternative — the Camino de Santiago and the narrow back roads through the wine country are quiet enough — and bike rental is available in Ponferrada and Villafranca. Walkers on the Camino need no transport at all; the long-distance footpath strings together most of the major sights of the region.