A castle was a fortified structure that was a locus of power and served as a dwelling place and sometimes as an administrative centre.

The castles of which old vestiges remain in Alsace are mostly those in the mountains, rather than in the plain. Born of the major forest clearing movement undertaken by the high nobility starting in the 10th century, fortified castles developed in Alsace due to the waning of Germanic Holy Roman Empire. They embodied the protection of the region and its inhabitants and gave concrete form to the lord's authority.

Emblematic figures of the region's mediaeval history, these castles towered over the plain and kept watch over the valleys, communication routes and sometimes the abbeys. To the delight of many a visitor, a great deal of them have withstood the test of time, as they were made of stone from the 12th century onwards.

Today, their impressive ruins inspire respect and admiration.