I noticed that all the big sports have their hallowed ground. Baseball has got Wrigley field, soccer has Old Trafford. It's strange that none of the combat sports has their own purpose built arena, not even boxing. This is what a sumo stadium in Japan looks like. Basically smaller and enclosed and more intimate setting with the crowd. I should think it also provides much better acoustics and viewing angles too, as opposed to an all purpose olympic/track and field stadium. This would help bring more brand recognition to MMA. These places would be known as "fight halls" or something like that.