Four years have passed since the RTRI's Large-scale Low-noise Wind Tunnel was completed at Maibara in 1996. This wind tunnel was built to study aerodynamic noise and aerodynamic phenomena for high-speed trains and develop their reducing measures. This wind tunnel has two excellent features: one is the extremely low background noise which makes it possible to measure the noise generated from a model precisely and the other is a large and high-speed moving belt ground plane which enables the simulation of the flow between the model and the ground. This review reports the specifications of this wind tunnel and an outline of the tests performed over four years.