In 1960, US 301 was extended to its greatest extent, Sarasota to Farnhurst. The part from near Bowie north to Baltimore reverted to MD 3, and US 301 was extended east along US 50 from near Bowie over the Chesapeake Bay Bridge to Queenstown. There it split to the northeast, replacing MD 71 to the Delaware state line. In Delaware, it continued concurrent with DE 71 to Middletown. There it split into a one-way pair on two two-way roads. US 301 northbound turned east at Middletown along DE 299, then running north on US 13 to its end at Farnhurst at I-295 - the Delaware Memorial Bridge approach. Southbound US 301 began at the same place, but only used US 13 to the DE 71 junction near Red Lion. From there it followed DE 71 all the way to Maryland, rejoining northbound at Middletown. In the early 1970s, the northbound alignment was modified, continuing north on Middletown with DE 71 across the Chesapeake and Delaware Canal on the Summit Bridge. After crossing the canal it continued north on DE 896 to Glasgow, where it turned east with US 40 to its merge with US 13 at State Road. In the mid-1980s, both directions were moved to run east from Mount Pleasant to US 13. Then in 1992, AASHTO approved relocating both directions to the path northbound had followed, joining US 40 at Glasgow. Signage currently now indicates that US 301 ends there, but on November 14, 2006, the Delaware Dept. of Transportation (DelDOT) announced that a new four-lane US 301 bypass will be built. The bypass, which had been proposed since the 1950s, would go west of Middletown, alleviating traffic conditions in state's fourth most populous town, and then travel in a northeasterly direction, intersecting the current DE 896 near Boyds Corner and then terminate at DE 1 near the highway's Biddles Corner toll plaza. A spur route, also following the old 1960s highway route, will connect US 301 with the four-lane Summit Bridge just south of Glasgow. When built, the road, like Delaware Route 1 and I-95, will charge a toll to cover the costs of building the new bypass, which is heavily used by trucks between Philadelphia and the Washington, D.C. metro areas. This bypass opened to traffic on January 10, 2019.