The castle is a long, narrow structure that runs east-west on an exposed hilltop south of Sonvilier.
 The castle gate house is on the eastern side of site and is still visible.
 A large, round bergfried is south and west of the gate house.
 The tower has 3 meters (9.8 ft) thick walls at the base and was probably about 30 m (98 ft) tall though only part of the tower still exists.
 The living quarters and court stretch west of the gate house and bergfried.
 Portions of the walls of the chapel, stable and kitchens in the living quarters still exist.
 A map from 1617 indicated that there was a semi-circular tower as the western end of the castle, but no trace of the tower still exists.
The castle is a long, narrow structure that runs east-west on an exposed hilltop south of Sonvilier.  The castle gate house is on the eastern side of site and is still visible.  A large, round bergfried is south and west of the gate house.  The tower has 3 meters (9.8 ft) thick walls at the base and was probably about 30 m (98 ft) tall though only part of the tower still exists.  The living quarters and court stretch west of the gate house and bergfried.  Portions of the walls of the chapel, stable and kitchens in the living quarters still exist.  A map from 1617 indicated that there was a semi-circular tower as the western end of the castle, but no trace of the tower still exists.
Erguel Castle