The Château de Crussol stands on a dramatic limestone promontory directly across the Rhône from Valence, visible from most of the city and from the motorway. The ruins are reached from the village of Saint-Péray on the Ardèche side of the river — a bridge crossing and a 30-minute walk up the hill. The effort is worth it: the castle commands an extraordinary view of the Rhône valley in both directions, and the ruins themselves are substantial enough to give a real sense of the original scale.
The castle was built in the 12th century as a feudal stronghold controlling river traffic, and at its peak was one of the most significant fortifications in the region. The ruins include the keep, parts of the residential buildings, and the ruins of a chapel. Restoration work has stabilised the most vulnerable sections. The walk up is easy enough for reasonably fit visitors and the views from the top on a clear day extend to Mont Ventoux and the Alps.