The Savior Tower ( Спасская башня ) also has an entrance gate, which closes the Red Square together with the neighboring St. Basil's Cathedral from the south. It owes its name to an image of the Savior that once hung over the gate. The Savior Tower is 71 meters high and, like the Nicholas Tower, was built by Pietro Antonio Solari in 1491. However, it was then about half as high as it is today. The tower has roughly the current shape since a reconstruction in the years 1624–1625, when it was supplemented by a bell tower with a large tower clock . The latter was designed by Scottish architect and watchmaker Christopher Gallowaydesigned and is today the most famous architectural element of the Redeemer Tower. The clock's four dials - one on each side of the tower - date from 1852; each of them has a diameter of 6.12 meters. The high-precision clockwork occupies three floors of the tower, and a dozen bells below the top of the tower ring every quarter of an hour.