The currently closed section of the trail started at Lyttonsville Junction, about one mile (1.6 km) west of downtown Silver Spring. It went west on an unpaved, crushed stone surface passing over Rock Creek on a trestle to Chevy Chase and then to Bethesda through the 800-foot-long Air Rights Tunnel. It was closed in September 2017 for construction of the Purple Line and the extension of the trail to Silver Spring. It will reopen around 2022 as a paved trail from Bethesda to Silver Spring.