Harbor Island

Harbor Island is a man-made island in the mouth of Seattle, Washington's Duwamish Waterway where it empties into Elliott Bay. Built by the Puget Sound Bridge and Dredging Company, Harbor Island was completed in 1909, and at the time was the largest man-made island in the world, at 350 acres (1.4 kmē). Since 1912, the island has been used for commercial and industrial activities.

Warehouses, laboratories, and other buildings are located on the island.