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Our Top 10 Stops on A Fossil Road Trip

Ashfall Fossil Beds State Historical Park, Nebraska

At many fossil sites, scientists work for months to unearth bits of disconnected bone or ancient tracks imprinted in stone. Ashfall Fossil Beds Historical State Park, however, is the home to the largest number of mostly intact three-dimensional prehistoric animal skeletons in the world [source: Ashfall Fossil Beds State Park]. This is because, about 12 million years ago, a super volcano erupted in what is now Idaho. The volcano spread a giant cloud of ash over a wide area including the northeastern section of Nebraska where this park is located. As the ash was inhaled by the animals living in this area, they died over the course of several weeks and, because their bodies were then surrounded by the falling ash, their skeletons were well-preserved for millennia. In fact, some of them still have evidence of their last meals in their mouths or stomachs.

Today, visitors can see complete skeletons still in the Earth and watch all of the excavation work as it happens. An enclosed facility known as the Hubbard Rhino Barn has been built around the primary excavation site, so a visit is possible in all types of weather. More than 350 full skeletons and 25,000 fossil specimens have been unearthed belonging to animals such as a raccoon dog, a bone-crushing dog, a saber-toothed deer and a barrel-bodied rhino -- the most common animal at the site.

In addition to the rhino barn, visitors can also stop in at the fossil preparation lab where paleontologists are available to answer questions. Nature trails and picnic facilities are also available.