I'd keep fly'n right on by Oahu and go to Kauai. Redlite hit it on the head.. Waikiki aka "town" is a %$%$%$%$ show tourist trap. If you insist on Oahu check out Diamond head. The North Shore is another cool place but it's the surfer equivalent to montuak and can be a zoo. Kauai and the Napali coast are real gems. Sorry I don't have any fishing advice. When I went I was surfing not fishing.
Hike this.. trust me
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