When you imagine divers searching an old shipwreck, you'd expect something out of the Titanic where they come across jewels and fallen chandeliers.

But not in Sweden. Nope, these divers found cheese. Stinky cheese.

Researchers were exploring a historic royal shipwreck called the Kronan, just off the south-east coast of Sweden, when they came across something that smelled really, really bad.

Lars Einarsson told his local newspaper, Kvallsposten, that the divers found it "pressed into the clay" and when they moved near it, the smell was unbearable.

"That's when they small hit is. I certainly don't recommend tasting it. It's like a mixture of yeast and Roquefort… whose character lives on in their smell.

"It's a mass of bacteria," he added.

The cheese was unveiled earlier this week after divers spent two weeks exploring the ship from 1676. They also found 14 gold coins, a diamond ring and a significant amount of 17th century pharmaceuticals.

Historians believe that the royal ship tried to sail through rough weather and somehow ignited its gunpowder magazine, which blew off the ship's bow.

Not ideal.