If you notice giant marshmallows in Golden Gate Park on Sunday, don't alert your local Ghostbusters; it's just Marsha and Mellow, ambassadors to the San Francisco Hot Chocolate 15K & 5K.

The race, which benefits Ronald McDonald House Charities of San Francisco, takes off at 7:30am behind the Music Concourse in Golden Gate Park, winds through the park, along the Great Highway, and ends behind the de Young Museum. Road closures, which include Great Highway and a few park roads, are all listed on this map, and last as late as 11:40am.

Unfortunately for chocoholics, race registration is closed, but you can still donate to the cause.