Big Ben
St. Stephen's Tower is the tower at the western entrance to the Palace of Westminster in London. This is the main entrance used by visitors to the Palace of Westminster visiting in order to view the proceedings of the Houses of Parliament, or by British subjects wishing to lobby their MPs.
It is often erroneously stated that St. Stephen's Tower is the clock tower at the northern end of the Palace of Westminster, which houses the 13-ton bell Big Ben. This tower is simply referred to as The Clock Tower, or colloquially as Big Ben.