MD 808 begins at an intersection with Ridgeville Boulevard, the original route of U.S. Route 40 (US 40), in the Ridgeville section of Mount Airy. Main Street continues south as a municipal street to an intersection with MD 27 just north of that highway's interchange with Interstate 70 and US 40 (Baltimore National Pike). MD 808 heads north through residential subdivisions as a two-lane undivided road following the Carroll–Frederick county line on top of a ridge. South of Sunset Avenue, the state highway fully enters Carroll County. MD 808 continues north through the Mount Airy Historic District, where the highway crosses paths with the former right-of-way of the Mount Airy Loop of the Baltimore and Ohio Railroad. The state highway passes Buffalo Road, which forms the Carroll–Frederick county line for several miles, and Waterville Road before leaving the town limits. MD 808 passes through the hamlet of Dorceytown before reaching its northern terminus at an intersection with MD 27 (Ridge Road).
