In Boston, it follows the inner relief road, where it becomes "John Adams Way", which crosses the River Witham (where it is tidal) on the £220,000 Haven Bridge, which opened in June 1966. It passes the Esso "John Adams Way Service Station" on the right, close to two speed cameras in either direction and overshadowed by the floodlights of Boston United. There are traffic lights at a roundabout with the A1137/B1183 (for Horncastle), where the inner-relief road ends near the "Red Cow Hotel". Boston Shopping Park is on the left, and the road becomes "Spilsby Road" where it crosses the Maud Foster Drain at Bargate Bridge near Maud Foster Windmill. It passes Holy Trinity church on the left, and the "Mill Inn" which is close to Boston High School. The road has a roundabout with the A16 and becomes "Wainfleet Road". At the "Burton Corner" roundabout, Skegness is signposted in the direction of the A16. It passes the "Burton House" on the right, then passes the "Ball House Inn" at Willoughby Hills. It crosses the Hobhole Drain at Haltoft End where it passes the Freiston Centre for Environmental Education and the "Castle Inn". There are right turns for Butterwick and it goes through Benington becoming "Main Road" where it passes All Saints church and the "Admiral Nelson", then Leverton where it passes St Helena's church. Near to Leverton Highgate is the Traveller's Rest cafe, and "Three Horseshoes". It passes through Old Leake, and meets the B1184 near The Giles School and passes the "Bricklayer's Arms" and passes near to the "Angel Inn" in Wrangle, then the primary school towards Wrangle Lowgate.