The mainline of MD 18 consists of four internally suffixed sections. MD 18A runs from Love Point south and east through Stevensville to a
roundabout at Castle Marina Road in Chester. MD 18B extends from the same roundabout east through Chester, Kent Narrows, and Grasonville to US 50 in Queenstown. MD 18S has a length of between US 50 and US 301 in Queenstown. MD 18C comprises the easternmost of the highway from US 301 in Queenstown to MD 213 in Centreville. MD 18A's western terminus is at the beginning of state maintenance on Love Point Road just south of the community of Love Point at the northern end of Kent Island. The state highway heads due south as a two-lane undivided road through farmland. After meeting Old Love Point Road at an acute angle, MD 18A passes suburban subdivisions and
Kent Island High School. Love Point Road, which is
unsigned MD 835C, veers southeast to pass through the
Stevensville Historic District, which contains the historic
Cray House, the
Stevensville Bank building, and
Christ Church. MD 18A curves to the southwest as Business Parkway. The state highway expands to a four-lane divided highway ahead of the intersection with
MD 8. MD 8 continues south on the divided highway toward an interchange with US 50/US 301 (Blue Star Memorial Highway) just east of the
Chesapeake Bay Bridge while MD 18A turns east onto two-lane undivided Main Street. MD 18A curves around the southern edge of the Stevensville Historic District, intersecting Love Point Road, which is unsigned
MD 759B to the south, and the other end of MD 835C (East Main Street). The state highway passes Stevensville Middle School, crosses Cox Creek, and passes the Kent Island Shopping Center before reaching its eastern terminus at a roundabout with Castle Marina Road, which is unsigned MD 18H to the south. MD 18B begins at the same roundabout at which MD 18A has its eastern terminus. Piney Creek Road, which is unsigned MD 18T, splits to the east as MD 18B curves southeast and crosses over US 50/US 301. The state highway curves east again at an intersection with its old alignment, Postal Road, in Chester shortly before an intersection with
MD 552 (Dominion Road). MD 18B continues around the south end of Piney Creek before entering the hamlet of Kent Narrows, where the highway has a direct connection to eastbound US 50/US 301. The state highway also has an indirect connection to the westbound freeway via Piney Narrows Road, where it passes south of a
park and ride lot under the freeway serving
MTA Maryland commuter buses, immediately before crossing Kent Narrows on a
drawbridge adjacent to the US 50/US 301 crossing of the strait. MD 18B continues east through Grasonville, where the highway intersects Chester River Beach Road (unsigned MD 18V) and Nesbit Road (unsigned MD 835K), both of which provide full access to the freeway. Past Nesbit Road, the road passes southeast of the
University of Maryland Shore Emergency Center at Queenstown and the
University of Maryland Shore Medical Pavilion at Queenstown. The state highway continues through farmland before reaching its eastern terminus at US 50 (Ocean Gateway) just east of the US 50 – US 301 split in Queenstown. The two highways meet at a
superstreet intersection, so there is no direct access between MD 18B and MD 18S on the opposite side of the intersection. MD 18S begins at US 50 opposite MD 18B's eastern terminus. At the intersection with
MD 656 (Friels Road) and Outlet Center Drive, which heads into the Queenstown Premium Outlets, the state highway turns north and reaches its eastern terminus at a superstreet intersection with US 301 (Blue Star Memorial Highway). MD 18C begins at US 301 opposite the eastern terminus of MD 18S. The state highway heads northeast as Main Street through the town of Queenstown, where the highway intersects
MD 456 (Del Rhodes Avenue) and passes near the historic home
Bowlingly. After leaving the town, MD 18C's name changes to 4-H Park Road and the road passes through farmland. The state highway passes the namesake park of the
youth agricultural organization shortly after crossing Reed Creek. MD 18C passes by the historic home
Bachelor's Hope before the highway reaches its eastern terminus at MD 213 (Centreville Road) on the southwestern edge of Centreville. ==History==