A large enclosed platform, often circular or oval-shaped, designed to showcase theatre, musical performances, or sporting events. As opposed to stadiums, that are often designed to hold in excess of 50,000 fans, arenas are typically designed for crowds under 20,000, for sports that compete on smaller stages like basketball and hockey.
The word "arena" derives from Latin "harena", a particularly fine-grained sand that covered the floor of ancient arenas such as the Colosseum in Rome, Italy, to absorb blood. Arenas are typically composed of a large open space surrounded on most or all sides by tiered seating for spectators, and may be covered by a roof. The key feature of an arena is that the event space is the lowest point, allowing maximum visibility.
A number of ice hockey arenas were also designed for use by multiple types of sport, such as basketball. In many of these multi-purpose arenas, such as the United Center in Chicago and the Staples Center in Los Angeles, an insulated plywood floor is placed, piece-by-piece, on top of the ice surface, and then the basketball court boards are placed over that.