The Southampton Shoal is a former lighthouse site, where now just the platform and pilings remain. The pilings, in their degradation, have come loose.
If you sail on the bay, steer well clear of the Southhampton Shoal platform. The platform continues to disintegrate and become more dangerous.
Except at low tide, the broken pilings are submerged.
Please give the Southampton Shoal platform a wide berth. The photo below is looking towards the East so all these pilings are on the western side.
The platform sits at the southwest edge of Southampton Shoals, northeast of Angel Island in the San Francisco Bay. The platform is all that remains of the original lighthouse, which now hosts a bell which rings at a ten second interval. Also attached is a pole topped with a red light that flashes on for three seconds and then off for three.
STEER WELL CLEAR!