It is often referred to as the 'world's most iconic colliery'. And rightly so, as the architects Fritz Schupp and Martin Kremmer created a very special industrial complex here between 1927 and 1932. With a harmonious composition of red brick facades in a steel framework – a paragon of symmetry and geometry – the building still has great aesthetic appeal. In 2010 the Zollverein mine was the cultural and artistic centre of the European Capital of Culture Essen in North Rhine-Westphalia. Coal was mined and processed here for 135 years, before the mine was decommissioned in 1986. Founded in 1998, the Zollverein Foundation very quickly dedicated its attention to repurposing the complex and preserving the industrial monument. With great success: today, it is a cultural highlight in the Ruhr region and a living museum of mining history and the development of industrial architecture. Visitors following the Zollverein heritage trail will learn about the modernists of the 1920s and 1930s, the development of heavy industry and how 'black gold' was processed: preserved in all their glory here are the former separation plant, the coal bunkers and the coal washery, gargantuan machines and conveyor belts, seemingly endless rows of coke ovens and six imposing chimneys. The tour also includes models, films and installations. However, it is not only the design of the colliery that stands out. The Red Dot Design Museum housed at the complex has the world's largest collection of contemporary design and is now part of the World Heritage site. Every year, the coveted red dot is awarded for exemplary design.