- Nooksack Falls is a waterfall along the North Fork of the Nooksack River in Whatcom County, Washington. The water flows through a narrow valley and drops freely 88 feet into a deep rocky river canyon. The falls are viewable from the forested cover near the cliffs edge. The falls are a short 2/3 of a mile drive off the Mount Baker Highway, Washington (State Route 542). The falls were featured in the hunting scene of the movie The Deer Hunter.
- Hollow Earth (Wikipedia)
The Hollow Earth is an obsolete concept proposing that the planet Earth is entirely hollow or contains a substantial interior space. Notably suggested by Edmond Halley in the late 17th century, the notion was disproven, first tentatively by Pierre Bouguer in 1740, then definitively by Charles Hutton in his Schiehallion experiment around 1774.