What might have been a single, roving sideshow brought cars spinning donuts and spectators to a couple of prominent San Francisco intersections Saturday night and early Sunday.

San Francisco police broke up a sideshow just before midnight Saturday at the intersection of 13th Street and South Van Ness Avenue, as KRON4 reports.

Cars and spectators dispersed after doing some stunt-driving donuts, but as is the way with these things, the group soon reconvened elsewhere.

SFist observed a spontaneous sideshow take shape about 45 minutes later at the intersection of Market and Castro streets — not a common location for these types of activities. The intersection was briefly blocked by cars and spectators, with the 24-Divisadero bus pausing for about 10 minutes until the intersection cleared.

Police did not arrive in the area until after the cars had dispersed, at around 1:00 am Sunday, and it did not appear any arrests were made.

It's not clear if it was the same group of vehicles, but a third sideshow broke out that night on the other side of the Bay Bridge in Oakland around 3:30 am Sunday. As the Chronicle reports, that sideshow involved around 50 vehicles and broke out at 98th Avenue and International Boulevard.

The weekend's nice weather inspired more sideshow activity on Sunday. An SFist tipster observed more donut-spinning and spectators gathered in the Lower Haight around 6:55 pm Sunday. That sideshow happened at the intersection of Pierce and Haight streets.

Sideshow activity, which was once more just an East Bay phenomenon, has been occurring more in San Francisco in the last few years — including one that broke out during the week before Christmas.

Several sideshows in Oakland turned destructive and violent last year, with cars set on fire and, in once instance last May, a bystander who attempted to break up a sideshow was severely beaten by a crowd — an incident that was captured in multiple cellphone videos.