Solomons Island Road was one of the original state roads marked for improvement to form a statewide system by the Maryland State Roads Commission in 1909.
The highway was graded and surfaced as an improved dirt road from Owings south to Hunting Creek in 1910 and 1911 and from there to Prince Frederick between 1911 and 1913.
Solomons Island Road from Prince Frederick south to Solomons was graded and surfaced as a dirt road in 1913 except for two segments: a 14-foot (4.3 m) wide shell road was built through Solomons and a 14-foot (4.3 m) wide gravel road was built for 3.6 miles (5.8 km) through Lusby.
This highway was improved to a gravel road for its whole length and several dangerous curves were modified by 1919.
Solomons Island Road from Lothian to Edgewater was built as a 14-foot (4.3 m) wide gravel road in 1915.
The state road between Edgewater and Annapolis was also finished by 1915.

In 1910, the Maryland General Assembly authorized funding for the construction of a boulevard between Annapolis and Baltimore.
This boulevard, which would have a minimum road width of 16 feet (4.9 m), would begin in Annapolis, cross the Severn River, head northwest to Glen Burnie, and continue through Anne Arundel and Baltimore counties to the tracks of the Baltimore & Ohio Railroad in South Baltimore.
The newly formed Maryland State Roads Commission was placed in charge of constructing the new Baltimore–Annapolis Boulevard.
The boulevard was constructed as a 16-foot (4.9 m) wide macadam road from the Severn River north to Arnold and from Severna Park to Pasadena in 1910 and 1911.
The sections between Arnold and Severna Park and from Pasadena to Glen Burnie were completed in 1912.
The boulevard followed much of what is today MD 648, with the major difference being in Pasadena, where instead of following Waterford Road north to MD 177, the boulevard headed northwest along what are discontinuous segments of MD 915 to Lipins Corner.

Unrelated to the Baltimore–Annapolis Boulevard, the commission constructed a 14-to-18-foot (4.3 to 5.5 m) wide macadam road from Glen Burnie to Brooklyn, which was then in Anne Arundel County, in 1915.
In Brooklyn, the new highway connected with the south end of the Light Street Bridge that crossed the Patapsco River into Baltimore.
With a road completed from Annapolis to Baltimore, the roads commission suggested that it should not be required to complete a road between Glen Burnie and South Baltimore.
The commission asked the Maryland General Assembly to pass a bill releasing the commission from the responsibility of completing the highway from Glen Burnie to South Baltimore.
However, the Maryland General Assembly disagreed with the Maryland State Roads Commission and passed a bill in 1914 requiring the commission to finish the boulevard between Glen Burnie and South Baltimore.
The Baltimore–Annapolis Boulevard north from Glen Burnie to Baltimore was finished in 1916.
The final gap in the Baltimore–Annapolis Boulevard was filled when the first modern Severn River Bridge was completed in 1924.
This 1,850-foot-long (560 m) concrete bridge, which had a roadway width of 22 feet (6.7 m) and a steel bascule draw with a horizontal clearance of 75 feet (23 m), replaced a narrow one-lane bridge.
The entire length of the Baltimore–Annapolis Boulevard was widened to 22 feet (6.7 m) with a pair of 3-foot (0.91 m) wide concrete shoulders by 1927.
The highway's bridge over Marley Creek was rebuilt from a width of 16 feet (4.9 m) to 36 feet (11 m) in 1926.

When Maryland assigned state route numbers in 1927, MD 2 was designated between Solomons and Baltimore.
The route followed Solomons Island Road from Solomons to west of Annapolis, where it ran concurrent with US 50 into the city on West Street.
MD 2 passed through downtown Annapolis on College Avenue and King George Street before it left the city on the Severn River Bridge and continued north along Baltimore–Annapolis Boulevard to Glen Burnie.
From Glen Burnie, MD 3 continued along Baltimore–Annapolis Boulevard while MD 2 headed north to Baltimore and connected to Potee Str
Solomons Island Road was one of the original state roads marked for improvement to form a statewide system by the Maryland State Roads Commission in 1909. The highway was graded and surfaced as an improved dirt road from Owings south to Hunting Creek in 1910 and 1911 and from there to Prince Frederick between 1911 and 1913. Solomons Island Road from Prince Frederick south to Solomons was graded and surfaced as a dirt road in 1913 except for two segments: a 14-foot (4.3 m) wide shell road was built through Solomons and a 14-foot (4.3 m) wide gravel road was built for 3.6 miles (5.8 km) through Lusby. This highway was improved to a gravel road for its whole length and several dangerous curves were modified by 1919. Solomons Island Road from Lothian to Edgewater was built as a 14-foot (4.3 m) wide gravel road in 1915. The state road between Edgewater and Annapolis was also finished by 1915.
In 1910, the Maryland General Assembly authorized funding for the construction of a boulevard between Annapolis and Baltimore. This boulevard, which would have a minimum road width of 16 feet (4.9 m), would begin in Annapolis, cross the Severn River, head northwest to Glen Burnie, and continue through Anne Arundel and Baltimore counties to the tracks of the Baltimore & Ohio Railroad in South Baltimore. The newly formed Maryland State Roads Commission was placed in charge of constructing the new Baltimore–Annapolis Boulevard. The boulevard was constructed as a 16-foot (4.9 m) wide macadam road from the Severn River north to Arnold and from Severna Park to Pasadena in 1910 and 1911. The sections between Arnold and Severna Park and from Pasadena to Glen Burnie were completed in 1912. The boulevard followed much of what is today MD 648, with the major difference being in Pasadena, where instead of following Waterford Road north to MD 177, the boulevard headed northwest along what are discontinuous segments of MD 915 to Lipins Corner.
Unrelated to the Baltimore–Annapolis Boulevard, the commission constructed a 14-to-18-foot (4.3 to 5.5 m) wide macadam road from Glen Burnie to Brooklyn, which was then in Anne Arundel County, in 1915. In Brooklyn, the new highway connected with the south end of the Light Street Bridge that crossed the Patapsco River into Baltimore. With a road completed from Annapolis to Baltimore, the roads commission suggested that it should not be required to complete a road between Glen Burnie and South Baltimore. The commission asked the Maryland General Assembly to pass a bill releasing the commission from the responsibility of completing the highway from Glen Burnie to South Baltimore. However, the Maryland General Assembly disagreed with the Maryland State Roads Commission and passed a bill in 1914 requiring the commission to finish the boulevard between Glen Burnie and South Baltimore. The Baltimore–Annapolis Boulevard north from Glen Burnie to Baltimore was finished in 1916. The final gap in the Baltimore–Annapolis Boulevard was filled when the first modern Severn River Bridge was completed in 1924. This 1,850-foot-long (560 m) concrete bridge, which had a roadway width of 22 feet (6.7 m) and a steel bascule draw with a horizontal clearance of 75 feet (23 m), replaced a narrow one-lane bridge. The entire length of the Baltimore–Annapolis Boulevard was widened to 22 feet (6.7 m) with a pair of 3-foot (0.91 m) wide concrete shoulders by 1927. The highway's bridge over Marley Creek was rebuilt from a width of 16 feet (4.9 m) to 36 feet (11 m) in 1926.
When Maryland assigned state route numbers in 1927, MD 2 was designated between Solomons and Baltimore. The route followed Solomons Island Road from Solomons to west of Annapolis, where it ran concurrent with US 50 into the city on West Street. MD 2 passed through downtown Annapolis on College Avenue and King George Street before it left the city on the Severn River Bridge and continued north along Baltimore–Annapolis Boulevard to Glen Burnie. From Glen Burnie, MD 3 continued along Baltimore–Annapolis Boulevard while MD 2 headed north to Baltimore and connected to Potee Str
Maryland Route 2