From typicallyspanish.com

Costa Blanca
Spanish Civil War bomb found in waters off Dénia
By h.b.
Feb 7, 2008 - 8:29 AM

A bomb dating from the Spanish Civil War has been found by divers off Dénia, Alicante. The bomb is a metre long and 40 cms across and was found in the area known as Les Marines.

It’s now covered with growth from the sea bed. Experts think it would have been an aviation bomb and that its explosive cargo probably remains intact. Civil Guard divers have taken photos of the find so that experts can better decide what to do next.