原尻瀑布，丰后大野

Harajiri Falls owes its dramatic form to the massive eruption of Mt. Aso approximately 90,000 years ago. The pyroclastic flow that resulted cooled and hardened into columnar rock formations, which were gradually eroded by the Ogata River to produce the wide, horseshoe-shaped cascade visible today. The falls sit on the Ogata Plain within Oita Prefecture in southern Kyushu, and have been designated one of Japan's Top 100 Waterfalls by the Ministry of the Environment, as well as one of Oita Prefecture's Top 100 Scenic Spots.

The falls measure approximately 20 meters high and 120 meters wide, and their horseshoe shape — set against the surrounding flatlands — has earned them the nickname the "Niagara Falls of Japan." Unlike many waterfalls tucked away in mountain valleys, Harajiri sits in the middle of open farmland, surrounded by rice paddies and rural fields, making the sight of a large waterfall appearing out of the countryside a genuinely distinctive experience.

Visitors can cross the wooden suspension bridge for a frontal view of the full cascade, then follow a circular walking path that leads above the falls and down to the basin below, where the mist and sound of the water create a close and immersive encounter. The suspension bridge, known as Takimi-bashi, stretches 90 meters in length and sways noticeably underfoot. Swimming in the basin is not permitted.

A 73-meter stone arch bridge known as Harajiri Bridge, built in 1923 with 5 arches, stands 500 meters upstream and is worth a short detour. At the adjacent roadside station, visitors can dine on regional specialties including Dango Jiru (dumpling soup) and try Kabosu soft-serve ice cream, made from a citrus fruit native to Oita Prefecture.

Entry to Harajiri Falls is completely free, with no admission fee required. The falls are located at 410 Ogatamachi Harajiri, Bungoono, Oita, approximately 3 km (about 20 minutes on foot) from Ogata Station on the JR Hohi Line. From Oita Station, the train journey to Bungomori Station takes roughly one hour, from where a local bus or taxi can be arranged, though services are infrequent. Renting a car is the most practical option, as public transport connections to the falls are limited.