Burg Sponeck in Sasbach

Burg Sponeck rises above the Rhine near Jechtingen, a ruined hilltop castle perched on a rocky spur 202 metres above sea level. The spur once jutted into the river on three sides, making attack possible only from the east. After the Rhine was straightened in the 19th century the water moved two hundred metres west, leaving the rock now surrounded by land. Beneath the castle lie the remains of a late Roman fort built around 370 under Emperor Valentinian I. The fort’s walls, towers and buildings were arranged to fit the rocky outcrop. A strong eastern wall, 1.6 metres thick with two corner towers, guarded the highest point where traces of another tower once linked the site to other forts along the Rhine and in Alsace. The small but solid enclosure, about forty by fifty metres, worked with nearby Breisach and forts in Alsace to control the river crossing and block Germanic raids. After 401 the fort probably served the Alamanni and later the Franks before falling into ruin, its strategic position only reused centuries later. Today the castle’s outline is marked by crumbling walls and a restored Roman section showing part of the stone curtain and two corner towers. The medieval core once had a keep roughly twelve by twelve and a half metres, a palace nine by seven, and a surrounding bailey with a residential tower. Nineteenth- and twentieth-century repairs added new stonework, but the surviving ruins still show where the old fort and castle once stood. Visitors walk among these fragments with views across the Rhine valley and the Kaiserstuhl hills beyond.