The Art Abloom Studio & Gallery, located on 735 Sir Francis Drake Blvd., was reported to be on fire at about 5:55 a.m. The blaze was controlled in about 30 minutes, a fire dispatcher said.
Ross Valley spokeswoman Joanne Lewis said that the damage to the gallery, as well as two apartments connected to the back of the building, are estimated at $700,000, with $500,000 in damage to the structures and $200,000 in damage to the content inside.
San Anselmo police said that authorities closed Sir Francis Drake Boulevard during the fire, but one of the two eastbound lanes was reopened at 8:25 a.m.
However, the second lane will be closed for most of the day as fire crews continue to clean up and investigate the scene, police said.
As of about 11:30 a.m., Ross Valley fire investigators were still trying to determine the cause for the fire, Lewis said.