Aurelianustoren, Medieval defense tower in Aarschot, Belgium.

The Aurelianustoren is a cylindrical brick tower, one of the few surviving remnants of Aarschot's 1360-1365 town wall, standing on a hill 40 metres above the Demer. Its lower part is clad in large dark brown and grey stone blocks under a projecting stone ledge; above, red and brown brick rises to a broken, uneven upper edge, pierced by a vertical arrow slit. A small plaque with the letters "KU" is fixed to the stone base.

It was built between 1360 and 1365 as part of the city's fortifications. When Austrian Emperor Joseph II ordered the demolition of city defenses in 1782, this corner tower was spared and survived the destruction of its surroundings.

The tower's name recalls the House of Orléans, the French royal line linked to Aarschot's medieval lords; the Dutch form Orleanstoren is still used alongside Aurelianustoren. The brick shaft carries a small plaque on its stone base, and the arrow slit above the ledge is the one opening a visitor can pick out from below.

Visitors can climb the spiral staircase and reach a viewing platform positioned above the tower's top. The climb offers good views of the city and river below from an elevated vantage point.

The tower was restored again in 2024, when its walls were returned to their original state and a spiral staircase was installed leading to a viewing platform 2.5 metres above the tower top. The small plaque on the stone base, now weathered, bears the letters "KU" and a line of text.