Ryumon Falls, Two-tier waterfall in Aira, Japan

Ryumon Falls cascades down in two distinct tiers with a height of roughly 46 meters and a span of about 43 meters, situated within the Tsukushi Lava Plateau. The formation displays two separate levels carved by water flowing over the volcanic stone surfaces.

The falls were named for their resemblance to the Longmen waterfall in China. Shimazu Tadatsune, lord of the Satsuma domain, wrote a waka poem about them, and the Confucian scholar Yasui Sokken visited the site. A Kannon statue built on a nearby hill by Shimazu Hisanaga, lord of Kajiki Castle, still stands. In 1990 the falls were chosen for Japan's Top 100 Waterfalls list.

The name comes from a resemblance to China's Longmen waterfall, and the falls appear in a waka by the Satsuma lord Shimazu Tadatsune and in Tachibana Nankei's travel account Saigūki. A Kannon statue built on a nearby hill by Kajiki castle lord Shimazu Hisanaga still stands. A legend tells of a giant snake rising from the pool where an old woman once washed clothes.

The falls lie along National Route 10 in Kajiki, Aira, and can be seen from the Kyushu Expressway. Water is drawn upstream for agriculture, so the flow is weakest from late May to September, especially in dry spells. A promenade and azalea garden were built around the falls in 1989.

The rock face is andesite: magma that intruded into the Kokubu Group strata during the Pleistocene and cooled, developing columnar jointing. About 1 km southeast, Mount Zaō is a volcanic neck formed by similar intrusion. The falls were named for their resemblance to the Longmen waterfall in China.