HMS Sussex had a valuable cargo when she sank 300 years ago in the Atlantic near the Spanish town of Cadiz.

She was carrying £1 million in coins which could be worth about £2.5 billion today.

But salvage experts have already spent millions in their efforts to locate the treasure, now thought to be well below the wreck. And if they do bring the booty ashore in Spain, it will have to be changed into euros.