Depending on the route, between 42 and 49 miles. It's about an hour taking this route: Take U.S. 101 SOUTH from Santa Rosa to SR-37 EAST to VALLEJO at EXIT 460. Take SR-37 EAST to VALLEJO.
591.78 kilometres (367.72 miles)
4,887.39 kilometres (3,036.89 miles)
521.27 kilometres (323.9 miles)
It is 376 miles according to Google Maps.