Merburg, Medieval castle ruin in Homburg, Germany.

Merburg is a castle ruin in Homburg perched on a hilltop with commanding views over the surrounding landscape. The remains show stone walls and fortification structures that reveal the original defensive design.

Merburg is a small ruined hilltop castle on the Malafelsen, a 257 m high spur above the Lambsbach valley near Kirrberg, now part of Homburg. Tradition places its construction in the Salian period between 1024 and 1080, though parts of the fortification date to the early 12th century, possibly on the site of a 10th-century refuge castle. Knights of Merburg are first named as ministeriales in 1172, and a Count Dietrich von Merburg is documented in 1179. The castle was probably abandoned in the late 12th century and was secured and conserved in its surviving state between 1975 and 1980.

The remaining structures of Merburg display medieval architectural techniques and building practices common in German defensive fortifications.

The ruin is accessible via marked paths with information panels explaining the layout of different sections. Visitors should expect uneven ground and steep slopes, especially after rain.

The castle stands on the Malafelsen, a rock rising only 12 metres above the Lambsbach valley at 257 m above sea level. Its octagonal keep had walls thick enough to suggest a height of at least ten metres, and a 75-metre ring wall enclosed it together with a solid house.