Colorado - US

The Upper Jurasssic dinosaur beds of the Morrison Formation near Cañon City, Colorado, were first excavated in 1877 by crews working for O.C. Marsh and E.D. Cope (e.g. Cope, 1877; Marsh, 1877). Some of the best known dinosaurs from the Morrison Formation were first named from specimens collected from there.

Many other genera and species were also named but most of these are no longer considered valid taxa. One exception is the little enigmatic Nanosaurus agilis, the first dinosaur named from Cañon City. The most profilic site. Marsh Quarry 1, has produced more than 12 species of dinosaurs.

Recent work has shown that the Morrison Formation at Cañon City can be devided into a lower Haplocanthosaurus zone and a upper Camarasaurus zone (Carpenter, 1997).