Bologa fortress, located at the foot of Vlădeasa Mountain, was one of the most important fortifications of medieval Transylvania. The first documented mention of Bologa fortress from 1304 is under the name of Sebuswar, a form also preserved in the subsequent mentions.
Bologa fortress was used without interruption until the 18th century, suffering many transformations and additions. This is distinguished especially by the circular donjon, one of the few preserved in Transylvania.
In 1399 the fortress was donated by King Sigismund of Luxemburg to prince Mircea cel Bătrân (Mircea the Elder), for his contribution brought in the anti-Ottoman wars. The fortress importance grew in the 17th century, after Oradea was conquered by the Turkish people, when the garrison of Bologa fortress stops the intrusion of the Turkish army through Crişul Repede pass. At the beginning of the 18th century, during the liberation war lead by the Transylvanian prince, Francisc Rakoczi II, against the Habsburgic domination from Hungary, the fortress was blown up by the soldiers in order not to fall into the hands of outlaws, the supporters of the liberation movement. At the middle of the 20th century the tower lost its roof, one of the last wooden elements preserved.
The fortress can be visited, not being enclosed.