Research divers are head to the sunken ship some believe belonged to the pirate Blackbeard to recover a cannon and other artifacts.
The North Carolina Department of Cultural Resources says the 12-week expedition is the most extensive effort yet.
There are differing opinions as to whether the ship is the Queen Anne's Revenge. But researchers who spent at least $2 million recovering artifacts off the central North Carolina coast haven't found anything to rule out that the ship belonged to Blackbeard.
Officials say besides the cannon, divers plan to recover two pewter plates and gold dust.
Historians believe the Queen Anne's Revenge ran aground in Beaufort Inlet in June 1718. State archaeologists have researched the shipwreck for 10 years, but are still waiting to find an indisputable link to Blackbeard.