The Citadel of Liège was the central fortification of the strategic Belgian city of Liège, Wallonia, until the end of the 19th century. It is located in the Sainte-Walburge neighborhood, 111 metres above the Meuse valley. Together with Dinant, Huy and Namur, the Citadel of Liège forms part of the so-called Meuse Citadels.
The first citadel was built on the heights overlooking the city in 1255. It was rebuilt in a pentagonal shape by Prince-Bishop Maximilian Henry of Bavaria in 1650. This fortress was destroyed by France shortly afterwards, then rebuilt in 1684. During the Napoleonic Wars, it was given five bastions in the style of Vauban. By the late 19th century, the citadel had become obsolete as a fort, replaced by the twelve forts of the Fortified Position of Liège, though it continued in use as a barracks and as a command post for the Fortified Position, contributing to the country's National Redoubt.
Wikipedia https://en.wikipedia.org/wiki/Citadel_of_Liège
Address Boulevard du 14ème de Ligne, 4000, Belgium
Coordinates 50°39'1.289" N 5°34'36.865" E