Japan National Route 51

National Route 51 is a national highway of Japan connecting Chūō-ku, Chiba and Mito, Ibaraki.

Route data

 * Length: 124 km (77.05 mi).

History
Route 51 was originally designated on 18 May 1953 as National Route 123, and this was redesignated Route 51 when the route was promoted to a Class 1 highway.