La Fábrica de Luz is the former coal-fired power station that supplied Ponferrada with electricity from 1920 to 1980, now converted into a museum of energy and a centre for contemporary art. The building itself — a vast brick hall with cast-iron stairways, oil-stained turbine pits, and rows of original control panels — is half the attraction; the rest is exhibits on the region's coal-mining past, which shaped the modern economy of El Bierzo more than anything else after Roman gold.
There are temporary exhibitions of contemporary art in the upper galleries and a small cafe. The site, on the bank of the Sil with a footbridge across to the medieval quarter, is the easiest way to understand how Ponferrada became a town of 60,000 people in the middle of the nineteenth-century mining boom. Closed Mondays.