i) births and deaths
11 March 1945: birth of Graeme Harper, director of three Old Who stories (including a large part of Warriors' Gate, for which he was not credited), ten New Who stories (counting Time Crash) and three Sarah Jane Adventures stories.
11 March 1952: birth of Douglas Adams, writer of The Pirate Planet (1978) and Shada (unbroadcast but would have been 1980), co-author of City of Death (1979) and script editor for Season 17 (1979-80); best known, of course, for other things.
11 March 1963: birth of Alex Kingston, who plays Professor River Song in New Who (2008, 2010).
11 March 1967: birth of John Barrowman, who plays Captain Jack Harkness in New Who and Torchwood.
ii) broadcast anniversaries
Also 11 March 1967: broadcast of first episode of The Macra Terror, which is the first to use the new opening sequence and therefore the first time that the current Doctor's face appears on screen before the story starts. The Tardis lands in a colony where people are behaving very strangely and are not on any account allowed to talk about the giant crabs.
11 March 1972: broadcast of third episode of The Sea Devils. The Master summons the Sea Devils from the sea; the Doctor repels them from the beach but they attack the prison.
11 March 1978: broadcast of sixth episode of The Invasion of Time, ending Season 15. The Doctor destroys the Sontarans with a D-Mat gun - hooray! Leela stays on Gallifrey with Andred - Boo!