Welcome to Dewey Beach, Delaware. Dewey Beach is one mile long and three blocks wide - bounded on the east by the Atlantic, on the west by Rehoboth Bay, Delaware Forests, rivers, parks and campgrounds provide the ideal setting for some of the state's best outdoor adventures. Canoeing. Fishing. Golfing. Biking. Hiking. Bird-watching. Horse-riding. Hunting. Boating. There's something for everyone throughout the year, from the 90-mile coastline to the hundreds of miles of nature trails inland.