The Pierre Shale formation was deposited during the Paleogene and Cretaceous periods about 70 million years ago. The region was covered by a deep sea—the Cretaceous Western Interior Seaway—which deposited massive amounts of shale on the seabed. Both the thick stratum of shale and embedded marine life fossils—including ammonites and skeletons of fish and such marine reptiles as mosasaurs, plesiosaurs, and extinct species of sea turtles, along with rare dinosaur and bird remains—were created during this time period. The area now known as Colorado was eventually transformed from being at the bottom of an ocean to dry land again, giving yield to another fossiliferous rock layer known as the Denver Formation.[58]
Split down the middle by the vast Rocky Mountains and jam-packed with national parks and wilderness areas, Colorado is an ideal travel destination for outdoor pursuits in every season. From skiing and whitewater rafting to hiking, biking and camping, outdoor activities are a way of life in the Centennial State. The state’s fun-loving culture attracts visitors looking for a laidback vacation too. After all, Colorado produces more beer than any other state and is one of only two states in the Union that has legalized marijuana for recreational use. Rich in historical and cultural attractions as well as in natural beauty, the best places to visit in Colorado have something special to offer every visitor.
The sun made us lazy, and after following Brian as he made his way upstream I found a wider expanse of sand and gravel, promptly plopping down on a pair of flip flops I had brought in my backpack as a make-shift seat. After identifying the northern harrier hawk over my head, and the savannas sparrows and red-winged blackbirds perched precariously on reeds across the water, I took out my knitting project. I didn’t have to worry about losing Brian; in the valley I could see for miles in both directions.
