The Collegiate Church of St. Bartholomew is a Roman Catholic collegiate church in Liège, Belgium. Founded outside the city walls, it was built in coal sandstone, starting in the late 11th century and lasting until the late 12th century. It underwent, like most ancient religious buildings, modifications through the centuries. Nevertheless, the Meuse Romanesque—Ottonian architecture character of its architecture remained deeply rooted. The 18th century saw the addition of two more aisles, the opening of a neoclassical portal in the walls of the westwork, and the French Baroque redecoration of the interior. The interior of the western section has recently been restored back to the original style.