We visited this park in April 07. Carnival offered this then as we ported at Calica. The bus was there waiting on us and it was only about 5 miles from the port. You can actually see the park from the Calica port. Since Carnival isn't offering this, you can easily catch a taxi from the port. Taxi cabs will be lined up waiting for passengers to get off the ship! Taxi fare should only be about $12 or less. I checked the website and admission is $62 for adults. It is worth every penny! We had such a wonderful time!
The park is like paradise! It's beautiful and more to do than you can fit into one day. Make sure you do the underground rivers (they are not totally undergound, plenty of daylight). Lifejackets are provided and they transport your valuables for free in a locked duffle bag to the end of the river area for you to pick up. There are restauants available reasonably priced. The lagoon area is near the dolphins and you can swim out near them. Your family will have a wonderful time!!!