The ruins of the 14th-century Olsztyn castle are one of the biggest attractions of the area. The castle, located on a hill, among limestone rocks, is part of the Trail of the Eagles' Nests. It belonged to a system of fortifications, built by King Kazimierz Wielki, to protect western Lesser Poland from Czechs, to whom Silesia belonged at that time. For some time, as a fee, it belonged to Prince Wladyslaw Opolczyk. Taken away from him in 1396, the castle was then handed by King Wladyslaw Jagello to a local nobleman, Jan Odrowąż of Szczekociny. The castle was invaded several times by Silesian princes in the 15th century, and with the advancement of warfare, its fortifications became obsolete. In 1655, it was captured by the Swedes, and since then, it became a ruin. In 1722, it was partly demolished, with bricks used to build a parish church at Olsztyn. Currently, only fragments of defensive walls remain. The most impressive still standing part of the castle is a 35-meter round tower, built in the 13th century, which served as a prison.
References:The trulli, typical limestone dwellings of Alberobello in the southern Italian region of Puglia, are remarkable examples of corbelled dry-stone construction, a prehistoric building technique still in use in this region. These structures, dating from as early as the mid-14th century, characteristically feature pyramidal, domed, or conical roofs built up of corbelled limestone slabs. Although rural trulli can be found all along the Itria Valley, their highest concentration and best preserved examples of this architectural form are in the town of Alberobello, where there are over 1500 structures in the quarters of Rione Monti and Aja Piccola.
The property comprises six land parcels extending over an area of 11 hectares. The land parcels comprise two districts of the city (quarters or Rione Monti with 1,030 trulli; Rione Aia Piccola with 590 trulli) and four specific locations.
Trulli (singular, trullo) are traditional dry stone huts with a corbelled roof.