Château d'Albon, Medieval castle ruins in Albon, France.

Château d'Albon is a ruined castle on a grassy motte at 388 m altitude, east of the village of Albon. Its square keep, 7.20 by 7.40 m with walls 1.65 m thick, rises three storeys from the hilltop. The masonry is grey sandstone veined with pink, laid in regular courses with thick mortar joints; a lighter patch runs up the centre and left corner. Below, a triangular rampart of rolled pebbles and molasse blocks enclosed the castral settlement.

The Counts of Albon built this fortress in the 11th century as their power base for controlling the region. The site became a key stronghold during the medieval period that shaped the political landscape of the Dauphiné.

The counts' castle chapel was rebuilt and enlarged in the 13th century; excavations from 1996–1997 uncovered its remains, including painted plaster and window glass. The name Albon passed to the family that took the title of count in the 11th century and, under Guigues V around 1142, the title of dauphin of Viennois.

The site is open year-round without entrance fees, making it easy to visit whenever you like. Marked trails guide you across the hilltop, helping you navigate and understand the ruins as you explore.

The keep is not the oldest structure on the hill: the earthen motte was raised first, in the 11th century, and the square tower of grey sandstone veined with pink was built several decades later, once the mound had settled. The tower measures 7.20 by 7.40 metres with walls 1.65 metres thick, divided into three timber-floored levels.