Burg Merten, Medieval castle in Eitorf, Germany

Burg Merten is a castle on a gently sloping hill surrounded by moats, built on a trapezoidal plan as a Kastellburg. The east side has a simple gate; parts of the late medieval ring wall remain, including a square tower at the northeast corner (only its ground floor survives) and the remains of two round towers on the west. The two-storey manor house with a Krüppelwalm roof was built in 1791 on the south side of the courtyard.

The castle was first documented in writing in 1247 and then changed hands several times over the centuries. In 1541 the Hatzfeld family established their Hatzfeld-Merten line there and made it their residence.

The name Merten passed through the Hatzfeld, Scheiffart von Merode and Spies von Büllesheim families; a 99-year inheritance lawsuit over the estate ended only in 1780, when the Spies von Büllesheim lost and also forfeited Schloss Allner. Since 1909 the castle has belonged to the Droste zu Vischering von Nesselrode-Reichenstein family, who bought it with the monastery and made Merten their main residence after World War I.

Burg Merten lies in the Merten district of Eitorf, on a gently sloping hill opposite Kloster Merten. Access is from the east through a simple gate; the site is enclosed by moats and a partly preserved late-medieval ring wall. The grounds are privately owned, so visitors should view the exterior from the public path.

In 1909 Count Felix Droste zu Vischering von Nesselrode-Reichenstein bought both the monastery and the castle; the family used the monastery as a summer residence and moved its main seat there after World War I. In 1930 the count also bought the east wing, which had until then served as the local school. The family sold the monastery after severe damage in World War II, but Burg Merten stayed in its possession.