Thousands of runners will take to London's streets on Sunday for the Big Half, a 13.1-mile half-marathon organised by London Marathon Events. Launched in 2018, the event aims to celebrate the capital's running community and make mass-participation running more accessible.
The event also includes the New Balance Big Relay, where groups of up to four people complete equal legs of the half-marathon distance together, and the Big Mile, a family-friendly run finishing at the same point in Greenwich. A free festival zone in Greenwich Park will be open to the public.
The race comes as a record 1.33 million people entered the London Marathon 2027 ballot, highlighting the growing popularity of mass-participation running in the capital.
Route and start times
The 13.1-mile route covers four of the six boroughs included in the full London Marathon: Tower Hamlets, Southwark, Lewisham and Greenwich. It begins near Tower Bridge, heads into Limehouse and towards Canary Wharf, then loops around to Wapping and back across Tower Bridge. Runners then pass through Rotherhithe and Surrey Quays before the home stretch in Greenwich, where the full London Marathon usually starts. The finish line offers a view of the Cutty Sark.
The Big Half officially starts at 8:30am, with staggered starts every 19 minutes. Participants have four hours to complete the race; those who don't finish in time must run on the pavement to complete it.
Spectator tips and transport
Good viewing spots include community cheer zones along the route, and an accessible viewing area near the finish line at Cutty Sark for spectators with disabilities. Tower Bridge and Cutty Sark can get extremely busy, so arrive early. The Big Mile begins at 2:30pm at Creek Road, heading towards Deptford, then loops back through Greenwich to finish at Cutty Sark.
Due to road closures, public transport is recommended. The stations closest to the finish line are Cutty Sark (DLR), Greenwich, Deptford and Maze Hill. For the start, Tower Bridge, Tower Gateway, Fenchurch Street and London Bridge are within walking distance.
Road closures
Multiple roads across Southwark, Tower Hamlets, Lewisham and Greenwich will be closed. Closures begin between 4am and 8am on Sunday and remain in place until between 2pm and 4pm the same day. Key closures include Tower Bridge Approach, Tower Bridge, Tower Hill, East Smithfield, Limehouse Link Tunnel, Aspen Way, The Highway, Butcher Row, West India Dock Road, Trafalgar Way, Churchill Place, North Colonnade, Upper Bank Street, Bank Street, Heron Quays, South Colonnade, Canada Square, Cabot Square, West India Avenue, Westferry Circus, Westferry Road, Salter Street, Limehouse Causeway, Narrow Street, Garnet Street, Wapping High Street, Thomas More Street, Tooley Street, Jamaica Road, Brunel Road, Salter Road, Redriff Road, Quebec Way, Canada Street, Surrey Quays Road, Lower Road, Evelyn Street, Deptford Church Street, Creek Road, Greenwich Church Street, College Approach, King William Walk, Nelson Road, Greenwich South Street, Greenwich High Road, Romney Road, Trafalgar Road and Haddo Street.
