Strawberry Spit (also Sanctuary Island) is a small artificial island in the San Francisco Bay's Richardson's Bay embayment of Strawberry Lagoon.

Historically the spit was a haul out area for harbor seals.

[1] A channel was built separating Aramburu Island from the mainland to isolate and therefore protect the seals from human disturbances.

[2] The landscape north and landward of Strawberry Spit is dominated by Ring Mountain, whose slopes are strewn with a multitude of boulders that include minerals such as mica, amphibolite and eclogite.

This Marin County, California–related article is a stub.