Burg Geroldstein, Medieval castle ruin near Dickschied-Geroldstein, Germany

Burg Geroldstein is a ruined lowland castle on a rock outcrop in the village of Geroldstein, part of Heidenrod in the Rheingau-Taunus-Kreis. The Wisper originally flowed around the rock on three sides until the saddle north of the castle was cut through in 1589 to shorten the river and use its drop for an ironworks. Surviving remains are a round tower, parts of a gatehouse and some wall fragments.

Burg Geroldstein was first mentioned around 1215 as Gerhartstein, probably named after a nobleman called Gerhart. The Geroldstein family held it as a fief from the Counts of Katzenelnbogen and built a small lordship around the village. A Trier electoral troop besieged it unsuccessfully in 1353. In 1479 it passed with Katzenelnbogen to Hesse, and after the line died out in 1569 it reverted to Hesse and was already described as a ruin in 1585.

The name Geroldstein probably derives from a nobleman called Gerhart, since the castle appears around 1215 as Gerhartstein. Around 1840 the ruin was recorded as Junkerburg, and on some maps the older castle is still wrongly labelled Burg Haneck, confusing it with its neighbour uphill to the east. Only a round tower, remains of a gate and some wall fragments survive.

The ruin is accessible via local hiking trails and its stable structures allow visitors to explore safely on foot. Sturdy shoes are recommended since the ground is uneven and some areas slope steeply, which is typical for sites built on hillsides.

Burg Geroldstein sits on a rock that the Wisper once flowed around on three sides, making it a near-island hill. In 1589 a low saddle north of the castle was cut through to shorten the river and use its drop to power an ironworks. Maps still sometimes label this older castle Burg Haneck, confusing it with the neighbouring site above.