I don't think any of these islands have that. Aruba is flat, no hills, Bermuda is the same. I think Jamaica is the island that has this. I don't recall seeing anything for St. Thomas or PR about it as well.
I thought Aruba and Bermuda were probably to flat.
Puerto Rico has mountainous areas.
I am going on Jewel of the Seas 12 night cruise in October.
These are the only places we go. I was hoping to find it in Puerto Rico at least.
I just returned from Bermuda and don't recall seeing anything there for ziplining, although I wasn't looking either. Contrary to what the poster above says, Bermuda has a very good share of hills/small mountains. Big enough for ziplining.
If you "Google" zipline and the island you will be visiting you can get more info. You'll have to "wade" through a lot of other stuff, but I did see some ziplining sites.
Have a wonderful cruise! (And be careful ) I wouldn't zipline if it was free !
"A truly happy person is one who can enjoy the scenery on a detour."