[2] Maryland Route 37 was the designation for what is now US 219 from the West Virginia state line near Redhouse north through Oakland to US 40 (now US 40 Alternate) at Keyser's Ridge in Garrett County.

[8][9][10] Maryland Route 41 was the designation for the highway between US 219 in Oakland and MD 38 in Deer Park in southern Garrett County.

[13] Maryland Route 44 was the designation for the access road from MD 56 south to Fort Frederick State Park near Big Pool in western Washington County.

[16] Maryland Route 46 is the former designation of the segment of I-195 between MD 295 and BWI Airport in Linthicum in northwestern Anne Arundel County.

[18] Maryland Route 48 was the designation for Pine Ridge Road from US 220 northeast to the Pennsylvania state line near Dickens in central Allegany County.

[13][26] Maryland Route 59 was the designation for Holter Road from US 340 in Jefferson north to MD 17 in Middletown in western Frederick County.

[13] Maryland Route 61 was the designation for a section of Old Forge Road from Antietam Drive eastward near Hagerstown in northern Washington County.

[13] Maryland Route 71 was the designation for the Blue Star Memorial Highway from US 50 in Queenstown to the Delaware state line near Warwick.

[40][41] Yellow Springs Road was relocated around Fort Detrick from Clover Hill southeast to connect with Rosemont Avenue in Frederick.

[15] Maryland Route 74 was the designation for Oppossumtown Pike from the old Frederick city limits on what is now Motter Avenue south of the US 15 freeway north to Poole Jones Road.

[52] Maryland Route 89 was the designation for Lower Beckleysville Road from MD 88 in Hampstead east to the Carroll–Baltimore county line.

[40] There may have been another segment of MD 92 from the Western Maryland Railway crossing at Edgemont north to Mong Road northeast of Smithsburg built by 1939.

[19] The highway was constructed as a concrete road from the National Pike south and west to near Glenelg by 1921 and completed in 1923.

[13] Maryland Route 100 was the designation for the portion of Old Frederick Road from MD 99 at St. Johns Lane near Ellicott City east to the Howard–Baltimore county line at the Patapsco River.

[19] Much of the highway was constructed as a macadam road from the river west to approximately the modern intersection of US 29 and MD 99 in 1923.

[57] Maryland Route 116 was the designation for what is now New Hampshire Avenue from US 29 and MD 108 in Ashton north to what is now Brighton Dam Road near Brinklow in northern Montgomery County.

[51] Maryland Route 119 was the designation for three disjoint segments of state highway in Germantown and Dawsonville in western Montgomery County.

[28] By 1978, MD 120 existed in two segments: the extant portion of Waters Road, and an L-shaped portion closer to I-270 that included Aircraft Drive northwest from MD 118 parallel to I-270 and a road that no longer exists heading northeast from the end of Aircraft Drive to a dead end at I-270.

[27] The highway was expanded to a four-lane divided boulevard from the city limits west to Gwynn Oak Park in 1940.

The eastern segment began at Vernon Road east of White Hall and extended to MD 23 in Shawsville.

The eastern segment followed Merrymans Mill Road from the reservoir reservation east to MD 146 near Jacksonville.

[54] The first segment of the macadam highway was built from MD 22 at Fulford or Shuck's Corner halfway to Medical Hall Road.

[13] Maryland Route 160 was the designation for Shuresville Road from MD 161 in Darlington northeast to US 1 at its crossing of the Susquehanna River at Conowingo Dam in northeastern Harford County.

[32][50] The highway was part of the original route of US 1; the road served as the western approach to the Conowingo Bridge that crossed the river upstream of Glen Cove.

[1] In 1928, US 1 was relocated to its present course on the western approach to Conowingo Dam; MD 162 was assigned to the Berkley Road portion of the old route.

[MD 164 2] Maryland Route 167 was the twice-used designation for two separate portions of Hammonds Ferry Road in northern Anne Arundel County.

[64] Maryland Route 180 was the designation for Annapolis Road from an entrance to Fort Meade near Odenton east to US 301 (now MD 3) in Millersville in western Anne Arundel County.

[35][67] Maryland Route 196 was the designation for Columbia Pike from US 29 in White Oak north to MD 198 in Burtonsville in eastern Montgomery County.

[22] The parallel divided highway Columbia Pike was completed from north of Paint Branch to Burtonsville in 1956; MD 196 was removed from Howard County the same year.

[65] The main portion of Columbia Pike on the west side of US 29 from north of Paint Branch to Burtonsville was transferred to county control between 1975 and 1977.