The first section of the Frederick Freeway opened from US 40 (now MD 144) east of Frederick to a temporary half-cloverleaf interchange with Patrick Street in 1956; this section featured a cloverleaf interchange with US 340. The remainder of the Frederick Freeway from Patrick Street to MD 26 was placed under construction in 1956. The highway was constructed as a two-lane freeway from just south of its interchange with Rosemont Avenue to its northern end near Hayward Road, where the freeway tied into existing US 15 at Harmony Grove. The freeway north of Patrick Street featured interchanges with Rosemont Avenue, Motter Avenue, and a westward extension of MD 26. When the Frederick Freeway opened in 1959, US 15 was moved to Washington National Pike north of Buckeystown Pike and north through Frederick along the Frederick Freeway. Market Street north of Evergreen Point through downtown Frederick to US 15 north of the city became a northward extension of MD 355; the section of Buckeystown Pike from the freeway to Evergreen Point became a section of MD 806.