The Great Saint Martin Church (German: Groß Sankt Martin, mostly Groß St. Martin, pronounced [ˈɡʁoːs ˌzaŋtʰ ˈmaʁtʰɪn] or [ˈɡʁoːs ˌzaŋtʰ maˈtʰiːn], regional colloquial pronunciation [ˈɡʁoːˌsaŋtⁿmaχˈtʰiːn], [ˈjʁuˑs ˌtsɪnt ˈmɛˑtəs]) is a Romanesque Catholic church in Cologne, Germany. Its foundations (circa 960 AD) rest on remnants of a Roman chapel, built on what was then an island in the Rhine. The church was later transformed into a Benedictine monastery. The current buildings, including a soaring crossing tower that is a landmark of Cologne's Old Town, were erected between 1150-1250. The architecture of its eastern end forms a triconch or trefoil plan, consisting of three apses around the crossing, similar to that at St. Maria im Kapitol.