Welcome aboard, Deborah!
I'm happy to hear that you're looking into one of Disney Cruise Line's Port Adventures. I always recommend taking Disney's Port Adventures versus trying to head out on your own. The ship always knows where you are and you can be sure that you're on a trip with the service you'd expect from Disney! All you have to do is show up and enjoy!
In Nassau, the ship pulls up to the dock, so you simply walk off the ship onto the dock. It's much easier than tendering in other ports. There is then a 15 minute walk from the dock to where you'll board the catamaran for the harbor cruise.
The
Nassau Harbor Cruise is a nice way to spend a couple of hours on the water. Since it is a short adventure, you might find when you log in to reserve your adventures that you are able to book not only this adventure but the
Discover Atlantis adventure too. Adventure times vary, so you'll see a few times listed to choose from once you are able to begin booking - 75 days prior to the cruise for first time guests.
I'd prefer to take the Discover Atlantis Port Adventure with Disney, versus trying to head there on my own. Taxis can run from $6 to $10 or more per person each way, depending on the driver, and you won't have access to much at the resort once you arrive on your own. Disney works with Atlantis to provide these excellent adventures that allow Disney cruise guests into areas normally reserved just for Atlantis guests.
As you get closer to your sailing, check out the possibility of taking both Port Adventures if the time lines up for your particular sailing, Deborah. Let me know if I can help with anything else before you set sail next year!