The Sinan Erdem Dome, formerly known as the Ataköy Dome, is a multi-purpose indoor arena that is located on the European side of Istanbul, Turkey. It has a seating capacity of 22,500 for concerts. For the sport of basketball, it has a seating capacity of 16,000, and for the sport of tennis, it has a seating capacity of 16,457 people, making it Turkey's largest multi-purpose indoor venue, and the third largest in Europe.