Namihaya Dome, indoor arena in Kadoma, Osaka Prefecture, Japan

Namihaya Dome is a modern multi-use arena in Kadoma that transforms with the seasons: a swimming facility with adjustable floor depth in summer, an ice skating rink in winter, and a gymnasium for sports competitions in spring and autumn. The venue holds 6,000 fixed seats with capacity to accommodate up to 10,000 people and features modern facilities including locker rooms, spectator seating, and display screens.

The dome was completed in 1996 and designed by renowned architect Mamoru Kawaguchi through his firm Kawaguchi & Engineers, which undertook many similar projects. Since opening, the arena has hosted numerous international sporting events, including the 2005 NHK Trophy figure skating finals and matches from the 2003 Women's Volleyball World Cup.

The nickname Namihaya Dome was chosen in 1995 from over 6,500 public entries submitted between September and October 1994. Since October 2015 the arena has carried the paid name Towa Pharmaceutical RACTAB Dome, after a generic-drug maker headquartered in Kadoma; RACTAB is the company's technology for orally disintegrating tablets.

The dome stands at 3-7-16 Mitsujima, Kadoma, a short walk from Kadoma-Minami Station on the Osaka Metro Nagahori Tsurumi-ryokuchi Line; Osaka City Bus also stops at the subway station. The main arena's use rotates by season, so check which configuration is running before travelling. The site also holds a sub-arena, a heated 50 m sub-pool open year-round, tennis courts and a youth baseball ground.

What sets this venue apart is its seasonal transformation capability: the arena floor is engineered to completely shift between seasons, featuring an adjustable foundation for swimming facilities in summer and regular surfaces for ice skating and sports competitions throughout the rest of the year. This technical flexibility makes it an unusual multi-purpose facility within the region.