In the early Mesozoic, the central valley that runs through the states of Massachusetts and Connecticut was a hot, semi-arid land similar to parts of the American Southwest. The valley was filled with lakes and braided rivers that provided enticing places for dinosaurs and other prehistoric animals to drink and feed.
Thousands of fossil footprints from these long-extinct wanderers can still be found throughout southern New England, and one of the better places to view them is at a site close to Mount Tom in Holyoke, Massachusetts, right next to the Connecticut River.
Time and the elements have worn at the red sandstone that holds the tracks. They can thus be a bit hard to see. But a careful eye can find hundreds of tracks. Several sets run parallel to each either, leading some paleontologists to suggest that these dinosaurs traveled in packs, though there is still much speculation about this point.
Since no bones have been found at the site, the exact identity of the trackmaker cannot be determined. Thus each type of track is given its own species name. The largest tracks are called Eubrontes. They are remarkably bird-like and were initially thought to belong to gigantic birds when they were first scientifically described in the 1800s. Other tracks found at the site include two smaller types of three-toed prints named Grallator and Anchisauripus, which may have been made by juvenile and young members of the same dinosaur species that left the Eubrontes prints.
The site also preserves fossil burrows, insects, plants, and solidified ripples from the ancient lake bottom.
The tracks can be found along a short trail that starts at a turn-out off of Route 5 in Holyoke. The main track site is a tilted slab of sandstone just next to the road. More prints can be found on rock slabs along the Connecticut River, though explorers should be careful on the slippery stone.