Burg Fürstenstein, Medieval castle in Albungen, Germany.

Burg Fürstenstein is a medieval fortification near Albungen with a distinctive residential tower made of sandstone. The tower features three stone levels and an upper timber-framed story, measuring approximately 13 by 8 meters.

The Counts of Bilstein probably built the castle in the 13th century. Count Otto II of Bilstein, the last of his line, sold his feudal holdings and then his allodial property to Landgrave Henry I of Hesse in 1301, bringing Fürstenstein to Hesse; it was subsequently pledged many times. From 1344 the Diede family held rights at the castle, and from 1596 until their male line died out in 1807 they were sole lords, calling themselves Diede zum Fürstenstein. In December 1807 King Jérôme of Westphalia confiscated castle and lordship and granted them to Pierre Alexandre le Camus, made Count of Fürstenstein; after the kingdom's end it returned to Electoral Hesse.

The castle is in private hands and cannot be visited, so the chapel added around 1600 to the side of the residential tower is seen only from outside. The Diede family, lords of the castle from 1596, called themselves Diede zum Fürstenstein after the estate.

Burg Fürstenstein is private property, so entry is not possible; the grounds and buildings can only be viewed from outside. The site lies on a rise at about 205 m above sea level on the right bank of the Werra near Albungen, a district of Eschwege. Approach on foot from the surrounding paths and keep to public ways.

The Diede family held this castle for over 460 years, an unusually long period of continuous ownership for a small fortification. This stability was rare in a region marked by frequent political changes.