The Château de Ramstein is a ruined castle in the commune of Baerenthal. This 13th-century castle was built by the lords of Falkenstein on the instructions of the bishop of Strasbourg to control the Zinselbach valley, probably in 1292. During the course of the 14th century, the lords of Ramstein transformed it into a den of brigands and it was destroyed in 1355 during a punitive expedition by the Strasbourgeois and their allies from Bern.
Below the castle can be seen two underground passages dug in 1936 by French military engineers as part of the Maginot Line. They were used as shelter by the local population during the battles of winter 1944-45. This site is currently closed to protect a colony of bats.
References:The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.