The Collegiate Church of St. Bartholomew is an historical building in Liège, Belgium. Founded outside the city walls, it was built in coal sandstone, starting in the late 11th century (the chancel) and lasting until the late 12th century (the massive westwork, with its twin towers which were reconstructed in 1876). 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.