The 1,600-square-foot mosaic, which consists of colorful geometric patterns, probably dates from the third or fourth century A.D., said Michael Hoff, a professor of art history at the University of Nebraska, whose team has been working since 2005 to excavate ruins in Antiochia ad Cragum, which was once a city on the southern coast of what is now Turkey.
First spotted in 2002 but uncovered just this summer, the mosaic is so large that Dr. Hoff and his team have exposed only about 40 percent of it. The rest will be unearthed next summer.
Dr. Hoff thinks the mosaic probably served as a decorative entrance to an adjacent bathhouse.
“It would have been used by all members of society from this town,” he said. “It was meant to be a beautiful parklike place where people could go and enjoy and walk around.”
Antiochia ad Cragum was founded by Antiochus IV of Commagene in the middle of the first century.
To date the mosaic accurately, Dr. Hoff hopes to uncover other artifacts in the area, like pottery.