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Gasometer Oberhausen: Christo was here
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As an exception, this time you can walk INSIDE Christo's art ( http://www.christojeanneclaude.net ). Oberhausen's "Gasometer" huge gas tank is one of the industrial heritage buildings in the Ruhr Metropolitan Region, which have been transformed into museums and venues for installations & performances. The dome inside is some 100 m high.
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