Thousands are set to attend the London Marathon this Sunday, supporting runners along the 26.2-mile course that begins in Blackheath and passes iconic landmarks such as Tower Bridge and The Mall. Significant road closures will be in effect throughout the day, with specific times listed for various routes; the planned M3 closure has been canceled to ease traffic. The London Underground and other transit services will run extra routes, though they are expected to be crowded, particularly near the marathon route, prompting attendees to plan accordingly.
