The US team are examining a site near Raqqa to see if contains the remains of the victims.
They are searching for the bodies of those killed by Mohammed Emwazi, the masked murderer known as Jihdai John who was filmed beheading multiple Westerners in sickening Isis propaganda films.
CNN reported the site was revealed from two British ISIS fighters who were captured in eastern Syria last month.
Like Emwazi, the informants, Alexanda Kotey, 34, and El Shafee Elsheikh, 29, were part of the “Beatles” terror cell.
And they are thought to have given details of where David Haines, 44, and Alan Henning, 47, James Foley, 40, Steven Sotlof, 31, and Peter Kassig, 31, were buried.
But identifying exactly where the grave is and the remains could prove difficult because of the sheer quantity of bodies spread across different locations.
A source said: “The two suspects have revealed clues about where the hostages are buried. But that may not be enough.
“The US wants to take the men back to the burial site areas so that they pinpoint the graves.”
The Beatles terror squad, so-called because of their accents, are thought to have murdered at least 20 people.
Former child refugee Elsheikh was a mechanic from White City in west London, while Alexanda Kotey hailed from Paddington.
In January 2017, US authorities named Kotey as a member of the cell and said they had imposed sanctions on him.
Emwazi himself was killed in a US air strike in 2015.
He appeared in a number of vile videos in which captives including British aid workers Mr Haines and Mr Henning were beheaded.
A fourth member of the cell, Amine Davis, was convicted of being a member of a terrorist organisation and jailed for seven-and-a-half years at a court in Silivri, Turkey, in May 2017.