The Heidelberg Tun (German: Großes Fass) is an extremely large wine vat contained within the cellars of Heidelberg Castle. There have been four such barrels in the history of Heidelberg; the present one has a capacity of approximately 220,000 litres (58,100 U.S. gallons) and was made in 1751. One hundred and thirty oak trees were reputedly used in its construction. It has only rarely been used as a wine barrel, and in fact presently enjoys more use as a tourist attraction, and also as a dance floor since one was constructed on top of the tun.
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