Photo: Maschinenjunge, [GFDL oder CC-BY-SA-3.0], Wikimedia Commons

Bottrop: Tetraeder

The so-called Tetraeder in Bottrop-Batenbrock is a freely accessible viewing platform, designed in the shape of a trilateral pyramid. It is situated on the 90-m crest of the pithead stocks Halde Beckstraße. The steel structure is supported by four 9 metres tall concrete piers, and when the visibility is good, you can see as far as the train station in Essen. Tetraeder was designed by Darmstadt-based architect Wolfgang Christi and structural engineer Klaus Bollinger. It was inaugurated on October 3, 1995 as a landmark of Internationale Bauausstellung Emscher Park.