Yorkshire
From Horton it enters North Yorkshire and goes through West and East Marton before a roundabout junction with the A56 after which the road passes Broughton. Afer passing through Broughton, the road meets the Skipton bypass at its western end, where it overlaps the A65 on its route between Kendal and Leeds. Skipton bypass was opened in 1981, providing welcome relief to the town, which often became a bottleneck as through traffic crossed in the town. The concurrent bypass crosses the B6265 north of the town, and then de-merges with the A65 to the east of the town.
The A59 was upgraded to primary status during the 1990s due to its increased perceived importance as an east-west route. It then passes over the Embsay and Bolton Abbey Steam Railway through a roundabout junction with the B6260 before rising up Beamsley hill, which was two lanes eastbound (uphill) and a single lane westbound during the incline - which was improved at various points during the 1980s. At the top of the hill, the road crosses into the Harrogate district. At this point, there is a long narrow descent on the edge of a huge ravine, down to the village of Blubberhouses.
The A59 then runs along the head of Fewston Reservoir and follows the route of a Roman road past the 'golf balls' at Menwith Hill, an RAF station. The road then declines towards Harrogate passing Kettlesing, and the Knabbs Ridge wind farm. In Harrogate it meets the A61 Ripon Road, and continues through the suburbs of the town, avoiding the centre. This is largely due to the history of the town - Harrogate's centre was traditionally known as 'Low Harrogate', whilst the A59 travels through 'High Harrogate'. This stretch of the route is claimed to be the busiest road in North Yorkshire. Part of this section travels across the Stray, an act-protected tract of grassy land which horseshoes around the town. The A59 then turns left at the Empress Roundabout, which is itself on the Stray, towards Starbeck - although traffic travelling towards York is directed onto the A661 to utilise the Harrogate and Knaresborough Southern Bypass (A658). The A59, however, continues to travel through Starbeck, then heads east to Knaresborough.
The remainder of the route is comparatively flat. From Knaresborough the A59 meets up with York-directed traffic from Harrogate on the A658, and skirts to the north of Goldsborough towards the A1(M). Originally the route went through the village of Flaxby and onto Allerton, but the route now travels a stricted east-west route and meets the A1(M) at its junction 47. The road then passes to the south of Green Hammerton. Originally it ended here, with the A66 routed down from Boroughbridge and going into York. Now the A59 itself heads towards York, travelling close to such places as Nun Monkton, Upper Poppleton and Moor Monkton before finally ending just to the west of the city walls at a zebra crossing at the junction of Bishopthorpe Road and Nunnery Lane which is the A1036.