Bodmin Jail, operational for over 150 years but now a semi-ruin, was built in the late 18th century, and was the first British prison to hold prisoners in separate cells (though often up to ten at a time) rather than communally. Over fifty prisoners condemned at the Bodmin Assize Court were hanged at the prison. It was also used for temporarily holding prisoners sentenced to transportation, awaiting transfer to the prison hulks lying in the highest navigable reaches of the River Fowey. Also, during the First World War the prison held some of Britain's priceless national treasures including the Domesday Book, the ring and the Crown Jewels of the United Kingdom.