Developer and basketball fan John Arrillaga donated most of the $11.5 million construction cost of the gym, with the city contributing $5.62 million.
Built at 600 Alma St., the single-story, 24,100-square foot gym hosts two full-sized basketball courts and four smaller versions; three volleyball courts; and last, but not least, four badminton courts.
Lockers, showers, and restrooms round out the amenities. Those who would rather watch than play can head for the bleachers, which can seat 664 people. The gym itself can hold up to 1,700 people.
The city asks that anyone attending the grand opening wear tennis shoes to avoid damaging the floor. Entrance is free, and the first 100 visitors will receive water bottles. For more information, call 330-2200.