Bologa Fotress, located at the base of Vlădeasa mountain, was one of the most important fortifications of medieval Transylvania. The first documentary attestation of Bologa fortress from 1304 is mentioning it under the name of Sebuswar.
The fortress was used without interruption, until the 18th century, undergoing many transformations and additions. It is particularly remarkable by the circular donjon, one of the very few preserved in Transylvania.
In 1399 the fortress was donated by King Sigismund of Luxembourg to the ruler Mircea the Elder, for his contribution in the anti-ottoman wars. The importance of the fortress increased in the 17th century, after the conquest of Oradea by the turks, when the garrison of Bologa fortress stops the turkish army from entering the Crişul Repede defile. At the beginning of the 18th century, during the liberation war led by the prince of Transylvania, Francisc Rakoczi II against the habsburg domination from Hungary, the fortress was blown up by lobonts, not to fall into the hands of the curuts, the supporters of the liberation movement. Legend has it, that among the ruins of the fort, the sword of Mircea the Elder is hidden.
The fortress is being rehabilitated.