There are a couple of threads going right now about the Castaway Cay 5k. I wanted to offer an alternative to those who don't run but still want to see all of the island. The bike rentals are great! They're very inexpensive, by Disney standards...$6 for an hour. Although, when I picked mine up, the lovely CM reminded me that "they have no clocks" and don't keep track of when the hour is up!! The trail is all level--no hills or anything--so it's an easy ride, even for smaller children. There are water stations all along the way and quite a bit of shade. Plus, there are lots of pretty places to take some great photos. I highly recommend it!