Ponferrada Castle is the city's defining monument, a broad-walled fortress associated with the Knights Templar and the Camino de Santiago. Its towers, courtyards, and heavy stone walls make clear why Ponferrada mattered as a defensive point in El Bierzo.
The castle is not just a backdrop for pilgrims; it is worth entering if you have time, because the scale is hard to grasp from the outside. Late afternoon light is especially good on the walls, and the old town around it gives the visit an easy rhythm.