Built in 1958, the tower's main sources of revenue are tourism and antenna leasing. Over 150 million people have visited the tower. FootTown, a four-story building directly under the tower, houses museums, restaurants and shops. Departing from there, guests can visit two observation decks. The two-story Main Observatory is at 150 metres (490 ft), while the smaller Special Observatory reaches a height of 249.6 metres (819 ft).