A66

A66 is a designation used for road numbers in several national transport networks. It is most commonly encountered as a road name in the United Kingdom and in Spain, where different road classes use the A66 or A-66 designation. The exact route and status vary by country and over time as roads are upgraded or renumbered.

In the United Kingdom, the A66 is a major trunk road in northern England. It runs roughly east–west across the north of England, connecting the northeast with the northwest. The road serves a mix of urban, rural, and industrial areas and provides a through route that links with other major highways, facilitating regional traffic and freight movement.

In Spain, the Autovía A-66 (Ruta de la Plata) is a long-distance highway that traditionally connects Seville in the south with Gijón in the north, crossing the interior of the Iberian Peninsula. Built and upgraded in stages since the late 20th century, its sections vary in construction type from autovía to autopista, with ongoing plans to complete or upgrade certain stretches to motorway standards.

Other uses of the A66 designation are less prominent and can include regional or proposed roads in other countries or historical references. When encountered, the exact alignment and status should be checked against current national or regional transport authorities.