Mittelburg castle, one of the four castles above Neckarsteinach, was probably built around 1165 by Conrad I of Steinach, the youngest son of Bligger II of Steinach. The castle was rebuilt into a Renaissance palace in the 16th century and Gothicized in the 19th century. Nowadays it is a home to the von Warsberg-Dorth family
References:The Citadelle of Quebec is an active military installation and official residence of both the Canadian monarch and the Governor General of Canada. It is located atop Cap Diamant, adjoining the Plains of Abraham in Quebec City. The citadel is the oldest military building in Canada, and forms part of the fortifications of Quebec City, which is one of only two cities in North America still surrounded by fortifications, the other being Campeche, Mexico.
The first fortifications in Quebec were built by the Governor General of New France Louis de Buade, and completed just in time for the Battle of Quebec in 1690.
After the British conquest in the second half of the 18th century, the problem of Quebec City's defences grew more acute.