Jewell (formerly Jewells) is an unincorporated community in Marin County, California. It is 24 meters above sea level. In the 1860s, the site was a dairy and pig farm owned by Omar Jewell. After the Northwestern Pacific Railroad was built nearby, Jewell sold land for the railway, and a request stop called Jewells was opened.
In the 1930s, small lots were created between Lagunitas Creek and Sir Francis Drake Highway. People from nearby cities built weekend homes there, and the settlement became known as Jewell.
The National Park Service later bought the community and removed the remaining residents. In 2018, an environmental group demolished the remaining houses and began restoring the creek to improve habitat for endangered coho salmon.