During the 12th century and onwards, Osthoffen became a fortified castle. Due to a siege lead by the Bishop of Strasbourg in 1410, fire raged through the building, depriving it of its 3rd floor. It was rebuilt as a Rennaissance estate and a private dwelling. More changes were made in the 18th century: courtyard walls were removed and new wide windows enlightened both the façade and the interior. The castle lost its towers during the French Revolution by order of the new authorities, one of the first works undertaken by the new owner was to rebuilt them. Today Château d'Osthoffen is a hotel and event venue.
Červená Lhota castle stands at the middle of a lake on a rocky island. Its picturesque Renaissance building is a destination of thousands of tourists every year. Its name Červená Lhota meaning 'red lhota' can be explained by the colour of the château"s bright-red roof tiles. There is also a park, where the Chapel of the Holy Trinity is located.
The existence of an original fortress on the site of today"s château is assumed from sometime around the middle of the 14th century. It was built on a rocky granite outcrop, which, after the damming of a stream and the filling up of a fishpond, became an island. The first written source is an entry into the land records from 1465, mentioning the division of the property of deceased Ctibor of Zásmuk between his two sons Petr and Václav.