Old Town Hall tower, Prague
This unique tower, which has a standard clock face at its top and an astronomical clock closer to street level, was built in the 14th century. It was a mechanical marvel of its time, with the astronomical clock displaying the date, seasons and other information with remarkable accuracy. Every hour, a mechanical procession of figures make their way out of a door above the astronomical clock face. The clock is easy to locate, especially for tourists, since the Old Town Hall houses the city's tourist information office. After the mechanical show, visitors can step inside the building to plan sightseeing expeditions or take a guided tour of the interior of this historic building.