Ostrý Castle, Castle ruin on Ostrý hill near Březno, Czech Republic

Ostrý Castle is a ruin on the summit of Ostrý hill (553 m) in the České středohoří, in the Březno cadastral area of Velemín, Litoměřice District. It had two parts: a fortified entrance corridor with a large polygonal bastion, where an 11.5 m barrel-vaulted cellar survives, and a palace on the rock top. Of the first gate only small wall fragments remain; the second gate, under a pointed arch, is better preserved and reached by a stairway probably from the 19th century.

Václav Kaplíř ze Sulevic founded the castle around 1430, and it was first mentioned in writing in 1436. Albrecht Libštejnský z Kolovrat bought it in 1508, and the Valdštejn family inherited it; a 1565 deed already calls it deserted. In the late 18th century a mason built a walled beer taproom and dance hall here with permission from the authorities.

The castle gave its name to the Osterští ze Sulevic, the family of its founder Václav Kaplíř ze Sulevic, who are recorded from 1436 as 'sitting at Ostrý'. In the late 18th century a mason, with the permission of the authorities, built a stone structure on the site and ran a beer taproom and dance hall there.

Access is via marked hiking trails from Březno, with the best visiting season being spring through autumn. Wear sturdy footwear as paths are uneven and ruins may have unstable sections.

In the late 18th century a mason, with the permission of the authorities, built a stone structure on the ruins and opened a beer taproom and dance hall there. After these ceased, the castle remained abandoned.