The state highway heads northwest as a two-lane one-way street to Woodmont Avenue.

MD 187 heads northwest from Woodmont Avenue as a four-lane highway with a center left-turn lane that passes through a five-way intersection with the eastern terminus of MD 188 (Wilson Lane), Arlington Road, and St. Elmo Avenue and leaves downtown Bethesda.

MD 187 intersects several entrances to the federal campus and passes to the east of the tiny village of Oakmont at its junction with Cedar Lane.

At its intersection with Executive Boulevard, MD 187 reaches its northern terminus, with Old Georgetown Road curving to the east as a county road and heading toward an intersection with MD 355 (Rockville Pike) just north of the North Bethesda station along Washington Metro's Red Line.

[1][2] MD 187 is a part of the National Highway System as a principal arterial for its entire length.

Between NIH and Charles Street the trail is co-located with the sidewalk on the east side of Old Georgetown Road.

[10] The Rockville and Georgetown Turnpike, which opened in 1818, included a descent into the valley of Rock Creek that bypassed MD 187's portion of the Rockville–Georgetown highway.

[26] This replaced an acute intersection with MD 355 north of Montrose Road now named Hoya Street.

[26] The divided highway was extended south to its present southern end north of Huntington Parkway in 1968.

[30] The highway's interchange with I-270 was reconstructed from a standard diamond to its present form with ramps to and from Rockledge Boulevard in 2002.