Tennis courts in Honolulu

There are some ten tennis courts in Ala Moanna Beach Park, the park itself is very beautiful and you have direct access to the ocean. The access is free and permanent, since the courts are lit at night, but you'll be lucky if you find a free court as soon as you get there. It works on first-come first-served basis, so you might have to wait in line. You could also use private courts, there is plenty of them, but not for free.