The Lion's Mound (, "Lion's Hillock/Knoll"; , "Lion of Waterloo") is a large conical artificial hill located in Wallonia in the municipality of Braine-l'Alleud (Dutch: Eigenbrakel), Belgium. King William I of the Netherlands ordered its construction in 1820, and it was completed in 1826. It commemorates the location on the battlefield of Waterloo where a musket ball hit the shoulder of William II of the Netherlands (the Prince of Orange) and knocked him from his horse during the battle. It is also a memorial of the Battle of Quatre Bras, which had been fought two days earlier, on 16 June 1815.