Japan National Route 155National Route 155 is a national highway of Japan connecting Tokoname, Aichi and Yatomi, Aichi in Japan, with a total length of. It serves as Nagoya's outer loop.HistoryRoute 155 was originally designated on 18 May 1953 from Nagoya to Toyama. This was redesignated as Route 41 in 1959. The current routing of Route 155 dates from 1963.