We will be visiting Oahu for one day (8am arrival & flight out at 10pm) in April 2014 and am looking for a sample itinerary. We will be coming over from Maui. The main reason for coming is to go to the aquarium. Yes, I know there is an aquarium on Maui, but we have special reasons for needing to visit the Waikiki one. We will not have a car either, so I would need tips on transport to the aquarium for opening (I believe 9am?) and then where should we go after that for the remainder of the day. Would it be advisable just to rent a car for one day to have more flexibility? Kinda like the idea of getting off the plane and just using public transport tho, but if there are must-see's in our one day that aren't accessible by public transport then we'd be open to renting a car. (Also, is public transport expensive? A quick car rental search shows about $35/day)
Thanks all !