The Zollverein Coal Mine Industrial Complex, designated a UNESCO World Heritage Site in 2001, is undoubtedly the most renowned industrial complex in the Ruhr and an essential monument to the age of coal and steel. Stretching over 100ha, it is divided into three areas: shaft 12, shaft 1/2/8 and the coking plant. The first coal mine shaft was dug here in 1847, the last mining activity took place in 1986 and the coking plant closed down in 1993.