Kapiolani Park is Honolulu's oldest and largest public park, a 160-acre expanse of banyan trees, lawns, and open space at the base of Diamond Head. Named for Queen Kapiolani, it was donated to the public in 1877 and has been the city's outdoor living room ever since. At the weekend it fills with joggers, yoga classes, cricket matches, kite flyers, and families.
The Waikiki Shell outdoor amphitheatre hosts concerts and the Honolulu Symphony on warm evenings. The Honolulu Zoo occupies the Diamond Head end of the park and is worth a few hours if you have children. The Saturday and Sunday farmers market near the bandstand is one of the best in the city. Walking through the park at sunset, with Diamond Head above you and the sound of the ocean nearby, is one of Honolulu's genuinely free pleasures.