Star Memorial Highway) just east of the Severn River Bridge in Arnold. After a diversion through the interchange, Governor Ritchie Highway continues north toward Baltimore carrying MD 2. History Original construction MD 450 from Bladensburg to the Severn River was proposed as one of the original state roads laid out by the Maryland State Roads Commission (MDSRC) in 1909. The first portion of the highway was built as a concrete road from Solomons Island Road (now MD 393) east to the city limits of Annapolis at Spa Road in 1914. The portion of the highway from Wagner Street at the city limits of Annapolis to the Severn River was proposed as the southernmost section of the Baltimore–Annapolis Boulevard (now MD 648), which was completed from the north side of the Severn River to Glen Burnie between 1910 and 1912. After litigation between the roads commission and Anne Arundel County, the result of which required the state to replace the bridge across College Creek, MDSRC constructed a new bridge across the creek in 1914 and 1915. The highway through the Naval Academy reservation from College Creek to the south side of the Severn River was built as a macadam road in 1916. The final gap in the Baltimore–Annapolis Boulevard was filled when the first modern Severn River Bridge was completed in 1924. This concrete bridge, which had a roadway width of and a steel bascule draw with a horizontal clearance of , replaced a narrow one-lane bridge. None of the highway from Bladensburg to Parole was completed by 1915. Construction of this highway started after a 1918 appropriation from the Maryland General Assembly specifically to construct the National Defense Highway, so named because it would connect the national capital with the Naval Academy. The first section built was from the Baltimore–Washington Boulevard east to approximately the location of the Baltimore–Washington Parkway in 1919. The second section of the Defense Highway, from there to near what is now MD 410 in Landover Hills, was started that same year and completed by 1921. Near Annapolis, another portion of the highway was built near the Annapolis Waterworks in 1920 and 1921. The western portion was extended east through Lanham to the Washington, Baltimore and Annapolis Electric Railway (WB&A) at Buena Vista near what is now MD 704 by 1923. The portion of Robert Crain Highway with which the Defense Highway crosses the Patuxent River