The state highway crosses Bennett Creek and Stillhouse Branch and passes through the village of Green Valley.

The state highway traverses Bens Branch in the hamlet of New London, which contains the Drummine Farm and Linganore High School on Old Annapolis Road.

After passing through Johnsville, which is home of the historic Kitterman-Buckey Farm, MD 75 curves to the east and crosses Beaver Dam Creek.

The state highway curves back to the north and traverses Haines Branch before crossing Sams Creek into Carroll County.

[1][2] MD 75 passes to the west of a cement factory before the highway enters the town of Union Bridge as Main Street.

The state highway intersects Locust Street in the center of the Union Bridge Historic District.

The state highway crosses Little Pipe Creek, then turns east onto Green Valley Road; Main Street continues north as a municipal highway that leads north to the historic Uniontown Academy and the village of Middleburg.

Through Linwood, the state highway is paralleled to the north by its old alignment, MD 800 (Watson Lane).

[1][2] A portion of MD 75 was originally the Liberty and Pipe Creek Turnpike from Libertytown to Union Bridge via Johnsville.

[4] By the end of 1911, the state road was completed from New Market to about 1 mile (1.6 km) south of Monrovia.

[18][19] MD 75 was relocated to the east of New Market when I-70 was upgraded to a freeway through the town, which included the modern I-70–MD 75 interchange, in 1973 and 1974.