The Gray Site is a Miocene-epoch assemblage of fossils located near the unincorporated town of Gray, Tennessee in Washington County, and dates from 7 to 4.5 million years ago. The Gray Fossil Site was discovered by geologists in May 2000. They were investigating unusual clay deposits turned up during the course of a Tennessee Department of Transportation highway project to widen State Route 75 south of its intersection with Interstate 26.
State Route 75 was realigned to protect the find by order of Tennessee Governor Don Sundquist, and a museum and research center at the dig operated by East Tennessee State University opened in August 2007.
The current dig at the Gray Fossil Site was determined to have been the location of a semi-circular sinkhole that once harbored a pond environment over a long period of time and is now yielding the remains of the ancient plants and animals that lived, watered, and died within the then watery sinkhole. Among the many vertebrate fossils found at the Gray Fossil Site are those of frogs, turtles and tapirs and recovered fossil records represent finds from approximately one percent of the total area of the Gray Fossil Site that has been explored --- and future fossil recovery from the entire site is projected to continue on for one hundred years.
The Gray Fossil Site is also the world's largest tapir fossil find and is yielding new and rare discoveries such as the most complete skeleton of Teleoceras yet found in eastern North America, a new species of red panda that marks only the second record of this animal in North America (the first red panda fossils found in North America come from the state of Washington), and a newly identified species of an ancient plant-eating badger.