Dungeness Spit is a 5.5-mile (8.9 km) long sand spit jutting out from the northern edge of the Olympic Peninsula in Washington, USA, into the Strait of Juan de Fuca. The body of water it encloses is called Dungeness Bay. The Dungeness Spit is entirely within the Dungeness National Wildlife Refuge and home of the Dungeness Lighthouse. It is the longest natural sand spit in the United States.
The spit is open to the public year around. Lise Ellner has completed a circumnavigation around the Spit.
It was first found by Europeans during the Spanish 1790 Quimper expedition. The name "Dungeness" comes from the Dungeness headland in England. The spit was named by explorer George Vancouver in 1792, who wrote: "The low sandy point of land, which from its great resemblance to Dungeness in the British Channel, I called New Dungeness."