Route 45 was posted on the bypassed sections piece by piece. The part south of the I-695 beltway was US 111 until the end, and 45 only fully replaced 111 in 1963. York Rd becomes Greenmount Ave at what appears to be an indeterminate point around 43rd St in North Baltimore. This is a remnant of the old 1888 Baltimore city limits. The annexed stretch of York Rd retained its name thereafter.
Marker is green as it appears to left.
A MD 45 Towson Bypass Marker. US 40 northwest of Frostburg. MD 46 was the number for the old BWI cutoff when the only access was via the B-W Parkway. Upon completion of I-195 in 1990 MD 46 was dropped. US 48 has its own page in the US highway section .