The Ryutetsu Nagareyama Line is a commuter railway in Chiba, Japan, that runs the short distance between Nagarayama and Mabashi stations covering only 6 stations. The Ryutetsu Line was once called the Sobu Nagarayama line, the Sobu Nagarayama Electric Railway, until it was renamed the Ryutetsu Line in 2008. Today it is usually called the Ryuden short for Ryutetsu Dentetsu or Electric Railway. Somewhat out of date and clunky, the train line survives to serve locals in the area just north of Tokyo, even though it only runs 6 km of track. After the introduction of the Tsukuba Express for which it parallels for a short distance, nevertheless the Ryuden continues operating albeit with fewer and fewer passengers.