The Tokyo Marathon is being held on the scale it was known for before the coronavirus pandemic for the first time in four years. It is one of the largest races in Japan.
About 38,000 runners started the race at the Tokyo Metropolitan Government building on Sunday morning in the chilly and cloudy weather.
Crowds of spectators gathered along the route and cheered, as no restrictions are in place this year.
The course passes through well-known Tokyo districts such as Asakusa and Ginza, and finishes at Tokyo Station.
One participant in his 60s has joined the race for the first time. He said he wanted to run the marathon and he is happy.
Roads have been closed along the route, and the last restrictions are scheduled to remain in place until 9 p.m.
Police in Tokyo have provided road closures information online. They are urging people to avoid driving their vehicles and instead use subway and other public transportation services.