Workmen tackling a leak in the churchyard of St Mary's Church in Hinckley stumbled upon a burial chamber thought to be 100 years old.
The two Severn Trent workers were tackling the leak beneath a footpath in the graveyard.
Mark Kirk, of the digging team, said:
When we struck it the bricks fell away and we saw water in there, it was full to the top. We dropped our pump in and when I looked in there I saw a skull looking back at me.
The church now plans to reseal the chamber and decide whether Leicestershire Police need to be informed.
More top news
A mild or very mild day tomorrow with sunny spells.
Dry and becoming breezy. Mild.
People in Wolverhampton and Birmingham are among the least likely in Britain to join the organ donor register according to one survey.