This impressive natural arch, 34m high and 59m wide, spans the River Ardèche, which once flowed around this promontory. In former times, only a narrow underground water course flowed beneath the arch. It is supposed that as a result of high river levels, the Ardèche abandoned its original course and flowed through this orifice which it gradually expanded, in so doing creating the Pont d'Arc. The beach here is a very popular swimming spot.