Roman remains have been uncovered by engineers carrying out work for Yorkshire Water.
The find was made near Pocklington and work was halted so archaeologists could be brought in.
Experts said they were excited by the finds which include human bones and pieces of pottery.
Archaeologist Paul Johnson, who is at the site, said ditches near to the location suggest there was a Roman settlement in the area.
A dig is now taking place with Yorkshire Water working around the archaeologists.
The finds will be sent to a specialist laboratory for further analysis.