The horseback riding is free and is located on the AKR property. You ride outside of AKR along the beach where you also see some of the locals homes and a small school. The horseback riding was a lot of fun and the horses were in pretty good shape. There was a little trash along the ride littering the water and beach but it was still enjoyable and the best part FREE!
The zip line is not free but you can sign up for the trip and they bus you up there and bring you back. You pay a little more and include the wildlife/gardens to it which we skipped.
You can take the water taxi just about anytime to watch the dolphins on Bailey's Key or pay for the experience or snorkel. They have daily free dolphin shows, RoatanMan was correct about the AKR guests really being outnumbered at the museum/show compared to other people from all over the island. Still, you never really feel like the resort itself is crowded with those visitors. They have free kayaks and canoes you can take whenever, shore diving, a nice pool and bar on the key ...Of course the fantastic covered porch with hammocks just outside your room....