Greenwich

Greenwich was an area of London in which the Royal Observatory was located. (PROSE: The Curious Case of the Miniature Menaces) Henrietta Goodheart was an astronomer at the observatory until 2006. (PROSE: Beautiful Chaos)

In 1894, the Paternoster Gang discovered an infestation of Gremlins in the Royal Observatory. They stopped the Gremlins from destroying the observatory and helped them find a new home at the bottom of the River Thames. (PROSE: The Curious Case of the Miniature Menaces)

In 2009, the Tenth Doctor found a spaceship trapped under Greenwich Park. (COMIC: Don't Step on the Grass)

Behind the scenes
Sophie Aldred (Ace) was born at Greenwich in 1962.

Aldred returned to Greenwich when filming Silver Nemesis. The battle against the Cybermen was filmed at the former site of the North Greenwich Gasworks, the then-future site of the O2 Arena.

Much of Dimensions in Time took place in Greenwich. The Seventh Doctor and Ace landed his TARDIS next to the Cutty Sark in November 1973. Also that year, Mike Yates drove the Third Doctor to meet Brigadier Lethbridge-Stewart's helicopter at the Old Royal Naval College's Grand Square on the Thames; after a quick hop to the college's Painted Hall, the Doctor emerged as the Sixth Doctor, the only time seen in this incarnation with Lethbridge-Stewart. In November of either 1973, 1993, or 2013, the Rani landed her TARDIS at the National Maritime Museum, whereupon Leela escaped. The Seventh Doctor, Ace, and K9 defeated the Rani's plans there.