The remains of the Castle can be visited
Hasenfratz Castle (Ruin)

The Hasenfratz Ruin, also known as Frazenhas, is on a hilltop near Gauselfingen in Baden-Württemberg. This hilltop castle, whose origins are shrouded in mystery, was built in the 12th century and abandoned approximately a century later. Today, the remains of the keep and some wall fragments are preserved.
The construction of Hasenfratz Castle is dated to around 1150. Its builders and inhabitants remain unknown to this day. The complex was abandoned around 1250. Originally, the castle grounds included a core castle with a keep, another building, as well as at least one moat and a defensive rampart.
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Location: 48.2760, 9.1541