Since the first marathon, the course has undergone very few route changes. In the first race, the course took a diversion around Southwark Park before re-joining Jamaica Road on the way to Tower Bridge and was routed through St Katherine Docks past the Tower Hotel, en route to the Tower of London and the cobblestoned stretch of road that in later years was carpeted, to help runners prevent injury on the uneven surface. In 1982, the finishing post was moved from Constitution Hill to Westminster Bridge due to construction works. It remained there for twelve years before moving to its present location at The Mall. In 2005, the route around the Isle of Dogs between was switched from a clockwise to an anti-clockwise direction, and at the route was diverted to avoid St Katherine Docks and the cobblestoned area near the Tower of London. In 2008, a suspected gas leak at a pub in Wapping diverted the course, but in 2009 the race followed the same path as in 2007.