Known for most of its length as Liberty Road, the state highway runs 44.10 miles (70.97 km) from U.S. Route 15 (US 15) in Frederick east to MD 140 in Baltimore.

The highway also serves as a major thoroughfare in the western part of Baltimore, where the street is named Liberty Heights Avenue.

[1][3] MD 26 begins at a partial trumpet interchange with US 15 (Catoctin Mountain Highway) on the north side of the city of Frederick.

MD 26 heads east as a four-lane divided highway through a mixed commercial and industrial area.

East of the river, the state highway meets the southern end of MD 194 (Woodsboro Pike) at the hamlet of Ceresville.

[1][4] MD 26 continues east through farmland where it crosses Israel Creek and passes through the village of Mount Pleasant.

West of Wesley Chapel Methodist Episcopal Church, MD 26 expands to a five-lane road with a center left-turn lane.

[1][4] MD 26 passes through the hamlet of Harrisonville and expands to a five-lane road with a center turn lane at Deer Park Road at the west end of Randallstown, where the highway passes the Choate House next to Wildwood Park.

MD 26 expands to a divided highway shortly before its partial cloverleaf interchange with Interstate 695 (Baltimore Beltway).

[1][4] MD 26 meets the western end of Northern Parkway and passes through Powder Mill Park just east of the city line.

MD 26 crosses over CSX's Hanover Subdivision railroad line just west of Druid Park Drive and Baltimore City Community College.

Liberty Heights Avenue continues east as an unnumbered street to MD 129 (Auchentoroly Terrace) at Druid Hill Park.

The highway was constructed from Eldersburg to Dorsey Crossroads, the site of the modern MD 97 junction, by 1923.

[11][14] The concrete road was extended to just east of Taylorsville in 1928, the same year a new section of the highway was paved through Unionville.

[9] Concrete shoulders were added to Liberty Road through Baltimore County and west to Eldersburg by 1926; the highway's macadam surface was also widened from US 15 to Ceresville in that time span.

[19] MD 26 received a new steel beam bridge with a 26-foot (7.9 m) wide roadway over the Patapsco River at North Branch in 1938.

[21] Reconstruction work continued into Carroll County when the highway was rebuilt from Liberty Reservoir west to Eldersburg starting in 1954 and from the eastern end of the Unionville relocation to Taylorsville beginning in 1956.

[25] In 1957, work began on relocating, widening, and resurfacing MD 26 through Eldersburg and between Taylorsville and Winfield.