Belluna Dome

Belluna Dome is a baseball stadium located in Tokorozawa, Saitama, Japan. It is home to the Saitama Seibu Lions, a professional baseball team.

The stadium has a roof over the field and the stands, like other indoor ballparks. However, it lacks a wall behind the stands so that natural air comes into the field. This makes it possible for home runs to leave the stadium, something not possible in typical domed stadiums.

The stadium was built in 1979 without the roof and named Seibu Lions Stadium as the new home field of the Lions that moved from Fukuoka to Tokorozawa that year. Initially an open air stadium, the installation of its roof took place in two phases: the first phase after the 1997 season, and the second phase after the 1998 seasons.