Gerstle Cove is one of the most popular dive sites along the Sonoma coast, and many Bay Area and Northern California dive shops use this site for certification classes. It's located 6 miles North of Fort Ross at Salt Point State Park. Driving North on Highway 1, you'll see the entrace clearly marked with a large sign on the right side.
Gerstle Cove is one of California's first underwater parks, and within a well-marked area, it is a marine reserve where all marine life, including abalone and all fish, are completely protected and off-limits to divers. The protected area is marked with a large yellow pole on the Northern shoreline, and a yellow rock on the Southern side of the cove. The boundary from these two poles mark the marine reserve.
Because this is a protected area, there is an abundance of marine life, and fish, abalone, and other sealife to see. Wolf eel have even been spotted here, and because it's protected, sealife seems to be more comfortable with divers around.
For divers still wanting to take fish or abalone, they can do so outside the cove. Make sure you're clearly across the boundary line and outside the cove before taking game. This area, like most other popular sites on the North Coast, are carefully watched and monitored by Fish & Game wardens, and the penalties for violating the laws are substantial.
Diving inside the cove reveals a rocky bottom strewn with boulders and a rugged terrain. Depths reach about 40 feet in the outer park of the cove, and deeper as you move farther out. As you exit the cove, the bottom becomes somewhat less rugged and the adventurious diver can reach depths up to 100 feet.
There is plenty of parking available here in the paved parking lot at the top of the cove, and there are also restrooms and showers available. There's plenty of hiking and beachcombing that can be done by non-divers as well.
Salt Point State Park is clearly marked at it's entrance, and is about 30 miles North of Bodega Bay and 19 miles North of Jenner. There is a day use fee (currently $8) to enter and use the park's facilities.
Gerstle Cove is protected from both Northern and Southern walls, so it's popular on days when other sites may be washed out. Visibility ranges from 10-25 feet. To get the current dive conditions here, visit the Salt Point Ocean Conditions web page which is updated regularly during Spring, Summer, and Fall months.