Jens Olsen's World Clock

Jens Olsen's World Clock or Verdensur is an advanced astronomical clock which is displayed in Copenhagen City Hall. The clock consists of 12 movements which together have 15,448 parts. The clock is mechanical and must be wound once a week. Displays include lunar and solar eclipses, positions of the stellar bodies, and a perpetual calendar, in addition to the time. The fastest gear completes a revolution every ten seconds and the slowest every 25,753 years.