The Nima Sand Museum features a large hourglass mechanism that automatically rotates from December 31 to January 1. It is designated the largest hourglass in the world, but is not officially registered in Guinness World Records. This museum officially opened in March 1991.

Sand_p1 This museum features sand comprising six large and small pyramids made of crystal glass. The world’s largest hourglass Sunagoyomi measures the duration of a year and is displayed in the center of the building.

via Wikipedia