Srebrna Góra Fortress was constructed in 1765–1777 when the territory was part of the Kingdom of Prussia. The fort is one of Poland's official national Historic Monuments and has been declared a rare example of a surviving European 18th century mountain stronghold.
The fortress in Srebrna Góra was built by the order of Frederick II, the King of Prussia. It was designed by Prussian architect Ludwig Wilhelm Regeler, aided by a number of Prussian military engineers. Minor additional works took place in the following years, but no major alterations were made; construction of a nearby flanked fort was begun but was quickly abandoned. The complex is composed of six forts, several bastions, and associated elements. The main fort of the complex is the central Donżon Fort on the Warowna Góra hill.
The complex is located on the heights of the Sudety Mountains, a body which forms a natural border between the Kłodzko Valley and the Silesian Lowlands. It controls the passage through the Silver Valley (Przełęcz Srebrna or Silberbergpass). The fort could shelter a garrison of 4000 soldiers, supplied to survive a year-long siege. It was defended by 264 artillery pieces. The fortress was intended to guard a route linking Prussian territories with Bohemian lands in the south, and thus help repel any possible incursions from Austria.
The fortress was never captured by the enemy while besieged. On 28 June 1807 it successfully resisted a siege by Napoleonic forces during the War of the Fourth Coalition; this was the only time the fortress was the site of an active battle. By 1860 it was declared obsolete and the garrison reduced in size; it was abandoned as an active military stronghold in 1867. The fortress has survived till modern day with relatively little modernization or damage, contributing to its valuable status as a historical monument of its era. It served as a military training grounds, and by the end of the 19th century was already a tourist attraction, with a restaurant opened in the fort by 1885.
During World War II the fortress was used as a prison for Polish officers imprisoned by the Germans. In 1973 a military museum was opened in the Fort.
References:The Château du Lude is one of the many great châteaux of the Loire Valley in France. Le Lude is the most northerly château of the Loire Valley and one of the last important historic castles in France, still inhabited by the same family for the last 260 years. The château is testimony to four centuries of French architecture, as a stronghold transformed into an elegant house during the Renaissance and the 18th century. The monument is located in the valley of Le Loir. Its gardens have evolved throughout the centuries.