Post Office Tower

The Post Office Tower, later known as the BT Tower, was a large tower in London designed to carry telecommunications traffic to the rest of England.

History
It officially opened in 1966. That year, the self-aware computer WOTAN occupied the top of the Tower and directed preparations for C-Day, its robot War Machines, and mind controlled human slaves from there. (TV: The War Machines)

Later in that year, with WOTAN defeated, Igrix the Kustollon left his spacecraft there. As the Ninth Doctor raced to get to Igrix's ship, unknown to both parties he passed his first incarnation's companions Ben Jackson and Polly Wright, both visiting the Tower. Both companions had had involvement in the C-Day affair. (COMIC: The Love Invasion)

In 2009, Rani Chandra believed that the strange lights that had been seen around the BT Tower were not lightning bolts, as reported in the Ealing Echo, but an alien spacecraft. However, Sarah Jane Smith had Mr Smith investigate and he determined that it was in fact lightning. (TV: The Mad Woman in the Attic)

By 2028, the WOTAN computer system was still located in the BT Tower. It was used by UNIT to monitor every other computer system in the world. (AUDIO: A Death in the Family)