Participants in four races must wear masks on some portions of the course, race officials announced in updates to the race's health protocols over the last two weeks. Stretches of Sunday's marathon, half marathon and 10K races, as well as all of Saturday's 5K, are in the Golden Gate National Recreation Area run by the National Park Service, and the agency announced last month masks are required indoors and in "crowded outdoor spaces" on park property amid the COVID-19 delta variant's nationwide spread.
Masks are required for portions of the San Francisco marathon.
Runners who don't wear masks could be fined by the National Park Service or face disqualification, race officials said. The National Park Service has said visitors who violate the mask requirement on its properties "may be subject to citations as appropriate."