"He’d never been inside the stadium before. Hundreds of seats were raised in stands around the field so that the spectators were high enough to see what was going on. At either end of the field were three golden poles with hoops on the end. "
-- Harry's first view of the Hogwarts Quidditch pitch (PS10)
Hogwarts students play Quidditch in a stadium located on the school grounds (PS11, CS10, PA15, OP19, HBP14).
The pitch is the field of play. The stadium comprises the pitch and the building surrounding it (which includes the spectator stands and commentator's box).
Tags: athletes competitions/competitors fans match outside Quidditch history Quidditch traditions spectators sports teams