Mushroom Stadium is a location in Mario Party Advance.
Description[]
Mushroom Stadium is a stadium located in the Desert Area of Shroom City. It has a red dome exterior that covers a set of stands and a pair of straight track and field lanes. It is where Bullet Bill goes for training.
In Mario Party Advance[]

Mario and Bullet Bill racing one another in Mario Party Advance
Mushroom Stadium is where Bullet Bill's quest, A Speeding Bill, takes place. In it, the player's character has to race Bullet Bill from one end of the stadium to the other. Mushroom Stadium is also featured in the Kamek Krew Live! quest, in which the player's character must find a venue where the Kamek Krew can perform. Bullet Bill allows the Kamek Krew play at the Mushroom Stadium because he is a big fan of theirs.