Mills. The US 50 divided highway started construction in 1950 and was completed between the Chesapeake Bay Bridge and Queenstown in 1952, including a new drawbridge over Kent Narrows. The 1933 bridge over Kent Narrows was dismantled in 1953. MD 18 was subsequently assigned to old US 50 between Stevensville and Queenstown, following its own alignment except for a concurrency with US 50 and later US 301 over Kent Narrows. Business Parkway was constructed in 1987 as a new alignment and northern extension of MD 8. MD 18 was extended west to Business Parkway and north on the divided highway to bypass the Stevensville Historic District in 1989; the old alignment was designated MD 835C. MD 18 also bypassed the center of Chester in 1989 by the construction of an overpass of US 50/US 301 just west of MD 552, replacing the intersection at Castle Marina Road. The latter improvement was part of the transformation of US 50/US 301 to a freeway from the Chesapeake Bay Bridge to Queenstown, which was completed in 1991. The upgrade included a new fixed high-level bridge over Kent Narrows for US 50/US 301, relegating the 1952 drawbridge to be used only by MD 18. In 1999, MD 18 was relocated to the north to use a new roundabout at Castle Marina Road in Chester; the old mainline was designated MD 18R. The MD 18 – US 301 junction in Queenstown was transformed into a superstreet intersection in 2003, resulting in the splitting of the MD 18C designation; MD 18S was assigned to the highway south of the junction. As part of the reconstruction of US 50 as a six-lane freeway from US 301 in Queenstown to MD 404 in Wye Mills, the Maryland State Highway Administration plans to construct an overpass of MD 18 over US 50 in Queenstown. MD 18 and US 50 would become connected by a pair of right-in/right-out interchanges. Access to eastbound US 50 would be via a new service road south of US 50 and connections with westbound US 50 would be made through Outlet Center Drive. As of 2011, the project has not been funded. Junction list Auxiliary routes MD 18 has 12 unsigned auxiliary routes. MD 18F, MD 18I, and MD 18U through MD 18Z are in Grasonville. MD 18G is in Queenstown. MD 18H, MD 18R, and MD 18T are in Chester. MD 18F is the