National Park Mystery Photo 22 Revealed: Apostle Islands National Lakeshore
There are many great places to paddle in the National Park System, whether you choose to go by canoe, raft, or sea kayak. And, there also are many park shorelines that are dotted with caves and grottoes.
This particular shot was taken at Apostle Islands National Lakeshore in Wisconsin. The "sea caves," as they're called, are tempting to explore via watercraft, and again in the winter when Lake Superior freezes over and you can actually walk into the caves.