The Timewheel (Hungarian: Időkerék) is one of the world's largest clepsammias, situated in Budapest next to City Park, right of Heroes' Square and behind the Palace of Art (Műcsarnok), on the site of a former statue of Lenin that now stands in Memento Park. It is made of granite, steel, and glass, and weighs 60 tons. The "sand" (actually glass granules) flows from the upper to the lower glass chamber for one year. The sand runs out on New Year's Eve and the Timewheel is then turned 180 degrees so the flow of the sand can resume for the next year. The turning is done by manual power using steel cables and it takes roughly 45 minutes for 4 people to complete the half turn. The Timewheel was unveiled on 1 May 2004 to commemorate the historic enlargement of the European Union that admitted Hungary (along with 9 other countries) to the EU.
The idea and the building of the Timewheel is marked by János Herner, the architectural design of the statue was done by István Janáky.