The Osaka Metro Nagahori Tsurumi-ryokuchi Line is an underground rapid transit system in Osaka, Japan, operated by Osaka Metro. It was the first linear motor rapid transit line constructed in Japan. Its official name is Rapid Electric Tramway Line No. 7 (高速電気軌道第7号線), and in MLIT publications, it is written as Line No. 7 . Station numbers are indicated by the letter "N".