As with the Annaberg Ruins just up the road, the Cinnamon Bay Nature Trails is a nice change of pace from the beaches. I appreciated the plaques set up to explain what purposes the buildings once had and it made it easier to imagine what it would have once looked like (there's even a small graveyard there). We didn't have time to explore then entire trail so I will most likely make a point to go back on our next visit (because you don't visit a place like St. John just once!).
If you appreciate history, I think it too is a place to put on your list. It's very accessible (just across from the Cinnamon Bay beach parking) and the heavily-treed canopy made it nice and cool.
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