National Route 55 spans much of the south side of Shikoku traveling southwest from Tokushima to
Cape Muroto along the island's coast. At the cape the route changes direction following the coastline still, but to the northwest towards Kōchi. and there are almost no steep slopes or curves, so it is also used as a driving course. Most of the road runs parallel to the east branch of the
Tosa Kaidō, a trade route established during the
Yamato period. Near
Anan National Route 55 runs along the coast, whereas the east branch of the Tosa Kaidō runs slightly inland. The scenic view zone along the route is also a typhoon-prone area, and traffic restrictions are often imposed from summer to autumn due to roadside collapses, falling rocks, and high waves. Traffic restrictions may also be put in place when a major tsunami warning is issued. Overall, the highway has a total length of . ==History==