Artificial islands protect piers on the Commodore Barry Bridge between Pennsylvania and New Jersey

Barrier islands are piles of rocks and dirt at the base of a pier designed to force a vessel to run aground before it hits the bridge.

Barrier islands are piles of rocks and dirt at the base of a pier designed to force a vessel to run aground before it hits the bridge.

Barrier islands are piles of rocks and dirt at the base of a pier designed to force a vessel to run aground before it hits the bridge.

Barrier islands are piles of rocks and dirt at the base of a pier designed to force a vessel to run aground before it hits the bridge.