This is the opening to Silver Lake, a dredged cove that PT boats used during
WWII to patrol for German submarines.
At one point in 1942, about one ship per day was sunk by German subs. Churchill
declared that German subs were to be called U-Boats, and Submarine was to be reserved for allied subs.
Some school classes, Jr. High I think, visited the island. Kayaking was their
Notice the sunk kayak.