Standing 150 feet above the Yellowstone River in Southern Montana and consisting of sandstone from the late Cretaceous Hell Creek Formation, 75 – 66 million years ago, is Pompeys Pillar National Monument. While we were staying in the area to see family, and being related to John Colter of the Lewis and Clark expedition, we made sure to check it out one evening. Although perhaps best known for the inscription left behind by William Clark of the expedition, this site boasts the markings of thousands of years of human occupation. I will share more about the monument in a minute, but first want to share a little about the interpretive center. Continue reading “Pompeys Pillar National Monument – Pompeys Pillar, Montana”