A college rowing teaming found a seven-foot-tall head that looks like something out of ancient Rome floating in the Hudson River.

The head is made of Styrofoam and cased in fibreglass, and nobody knows where it came from.

It "looked like something out of a futuristic dystopian movie," Marist College Crew coach Matt Lavin told Newsday. "I thought it was Lady Liberty's head."

It could be from almost anywhere. Known by Native Americans as "the river that flows both ways," the Hudson River's lower half is a tidal estuary, meaning it literally runs north and south.

"It's a mystery we're trying to solve," said Greg Cannon, the college's spokesman.

The most popular theory is that it's a theatre prop.

Whatever it is, it may have a matching body floating out there somewhere. If to scale, it would be 30 to 40 feet tall.

On their Facebook page, the rowing team dubbed the head their "new boathouse idol."