[1] It is located in the town of Iwaizumi, Iwate Prefecture, in the Tōhoku region of northern Japan.

Ryūsendō has an accessible length of 1,200 meters, making it the 62nd longest in Japan; however, its depth of 249 metres (817 ft) from the entrance to its lowest point is the 5th deepest in Japan.

The cave system includes at least four underground lakes, the third of which has a depth of 98 metres (322 ft), and the fourth of which (not accessible to the public) has a depth of over 120 metres (390 ft).

Its underground lake system was designated one of the "100 Famous Springs of Japan" in 1985 by the Ministry of the Environment.

[2] The adjacent Shin-Ryūsendō (龍泉新洞, "New Ryūsendō") caves nearby were discovered in 1967.