A fellow Geologist on Facebook posted the "what if" you could make pavers from columnar-jointed basalt. I posted these images on FB, so as to give casual readers an idea of what we were discussing - in some jest. The conclusion was (on my part) that basalt pavers would be neat, but because of access problems and logistics, it probably wouldn't work. The first 3 photos were from park areas, while the fourth is in a Wilderness Study area, 1 mile plus from any parking - even if it was legal.
This particular photo from Yellowstone was a scanned slide, taken by my Dad in the summer of 1980, while he and my Mom were on their last vacation together. He passed away that November.
A good friend went on a short vacation with his dad, brother, and son and got a number of photos of Devil's Tower in Wyoming.
The Aden Basalts - flood basalts from fissure eruptions - are located in southern Doña Ana County, New Mexico.
For those not familiar with columnar basalts, they usually form vertical, elongate polygons with 5 - 7 sides, during the cooling of surface and near-surface basalts in flows and volcano necks as you can see here. I seem to remember there being some columnar joints in some parts of the Palisades of the Hudson sill, but don't have any photos.