The London Marathon course is flat and fast. It starts in Blackheath, heads east through Charlton and Woolwich for three miles, turns west and passes the Cutty Sark in Greenwich after six to seven miles. It crosses the River Thames at Tower Bridge and then loops around the east end of London, past Canary Wharf in Docklands, before heading west again along the Highway and the Embankment to Parliament Square, Birdcage Walk and the final corner in front of Buckingham Palace.
The first London Marathon, held on 29 March 1981, finished on Constitution Hill between Green Park and Buckingham Palace. From 1982 until 1993 the race finished on Westminster Bridge with the Houses of Parliament in the background. But in 1994 repair work to the bridge meant the finish line was moved to The Mall where it has been ever since.
Apart from the finish, the London Marathon course hasn't changed much in its 32 year history. In 2005 it was altered slightly at 22 miles to avoid the cobbled area near the Tower of London, and that year the route around the Isle of Dogs between 14 and 21 miles was switched from a clockwise to an anti-clockwise direction.
In 2015 part of the course changed in the Canary Wharf area due to building works.