US 50's bypass of Berlin was completed in 1958. Salisbury Parkway (now US 50 Business) from MD 349 to Main Street was completed by 1964 and US 50's four-lane divided highway between MD 346's western terminus and the US 50–MD 346 intersection west of Berlin opened in 1965. MD 346 was assigned to the old alignment of US 50 from Salisbury to west of Berlin in 1966 and through Berlin in 1967.
The bypass of US 50 around Berlin was completed in 1958. The Salisbury Parkway (now US 50 Business) from MD 349 to Main Street was finished by 1964, and the four-lane divided highway of US 50 between MD 346's western terminus and the intersection west of Berlin opened in 1965. In 1966, MD 346 took over the old alignment of US 50 from Salisbury to west of Berlin, and in 1967, it was assigned responsibility for the road through Berlin.