Aichi Prefectural Gymnasium

Aichi Prefectural Gymnasium (愛知県体育館), also known as Dolphins Arena (ドルフィンズアリーナ), is a multi-purpose gymnasium in Nagoya, Japan, built in 1964.

Overview
Located on the site of the secondary enclosure of Nagoya Castle, it is host to numerous concerts and events. The gymnasium has 4,375 fixed seats and can accommodate an additional 3,032 on the floor for certain events, giving it a total maximum capacity of 7,407.

It won the 7th annual Building Contractors Society Award in 1966.

Professional Sumo's July Grand Sumo Tournament was held at the site every year from the second until the fourth Sunday in July. Beginning in 2025, the tournament will move to the nearby Aichi International Arena (IG Arena).

It is the home arena of the Nagoya Diamond Dolphins of the B.League. Dolphins acquired its naming rights (JPY 25 million, three years) in 2018.