Split Rock Lighthouse, Lake Superior near Beaver Bay, Minnesota. Completed in 1910, has been dark since 1969 except for an annual lighting on November 10 to commemorate sailors lost in Great Lakes shipwrecks.
Iguazu Falls - Both sides are amazing! Definitely do the boat ride to the foot of the Argentina side. And get a pano view of the falls from Brazil. make sure you get a visa first!...otherwise Carlos the taxi driver can take you across ;)