Montagne de Bueren
Montagne de Bueren is a 374-step staircase in Liège, Belgium. The staircase is named after Vincent de Bueren, who defended Liège against an attack by the Duke of Burgundy, Charles the Bold in the 15th century. It was built in 1881 to honour the 600 soldiers who died in the battle.
In 2013, Montagne de Bueren was ranked as #1 on The Huffington Post's list of Most Extreme Staircases.