State Route 116 (SR 116) is a 9.83-mile-long (15.82 km) state highway in the U.S. state of Washington, serving Indian and Marrowstone islands in Jefferson County. The two-lane highway travels east from SR 19 in Port Hadlock-Irondale across the Portage Canal to Indian Island and Marrowstone Island, turning north and ending at the entrance to Fort Flagler State Park. SR 116 was created in 1991 and follows the route of Flagler Road, built and paved in the 1960s.