re: Bermuda

rent a scooter if you are up for it and go to both ends of the island. I think they also rent golf cart type things now to tourists, but tourists can't rent cars.

crystal caves are cool.
We rented paddleboards at blue hole watersports by grotto beach resort, there is also a cave right there that is free to go in and you can swim in the water.
Beach hop from Elbow beach, down to around The Reefs resort. Best beaches in the world along that stretch.
Go to the Swizzle inn (2 locations) and get a swizzle. Henry VIII has good sushi.
climb to the top of the lighthouse
maritime museum
If you have time and budget, there is some of the best deep sea fishing in the world there depending on when you go. My friend runs sea wolfe sportfishing, The challenger is also a really good boat.