Eurydice was a French submarine, one of eleven of the Daphné class. On 4 March 1970, while diving in calm seas off in the Mediterranean, 35 miles (56 km) east of Toulon, a geophysical laboratory picked up the shock waves of an underwater explosion. French and Italian search teams found an oil slick and a few bits of debris, including a part that bore the name Eurydice. The cause of the explosion was never determined. All 57 crew were lost.