It's the most talked-about military site in the world. Just 18 miles southeast of Tehran, the Parchin military facility, suspected of housing a containment chamber to conduct high-explosive tests, has long eluded U.N. inspectors. But today, a research group in Washington has pinpointed on a satellite image what it says are its whereabouts. 

In November, the International Atomic Energy Agency reported that Iran had constructed a building at its Parchin military facility around 2000 to hold "a large cylindrical object" and that "a large earth berm was subsequently constructed between the building containing the cylinder and a neighbouring building, indicating the probable use of high explosives in the chamber." It added, "The Agency has obtained commercial satellite images that are consistent with this information." But the IAEA never released the images backing up its report.

When questions arose in February about the facility, The Atlantic Wire wanted to see what it looked like, so we asked our friends at the commercial satellite firm GeoEye if they had any imagery of Parchin and sent their images to analyst Paul Brannan at the Institute for Science and International Security (ISIS). Today, ISIS wrapped up its report and has identified the site mentioned in the IAEA report. To this day, Iran has consistently denied that it has engaged in nuclear experiments at the site.

"The building is located on a relatively small and isolated compound within the Parchin military site and has its own perimeter security wall or fencing," reads the report by ISIS founder David Albright and Brannan. IAEA officials have repeatedly requested to visit the site.

On Thursday, six world powers, the U.S., Russia, China, Britain, France and Germany, called on Iran to give U.N. inspectors unfettered access to Parchin, something it had refused to do in the past. Iran had publicly noted a willingness to cooperate with IAEA inspectors but the joint-statement called on the country to enter a formal agreement with the nuclear watchdog.  “We call on Iran to enter, without preconditions, into a sustained process of serious dialogue which will produce concrete results,” read the statement

The joint-statement was prompted, in part, by allegations that Tehran attempted to clean up radioactive traces leftover from secret nuclear work. On Tuesday, Iran's foreign ministry spokesman Ramin Mehmanparast rejected those allegations, telling reporters "this is mainly public speculation and not based on logic," according to the Associated Press. Mehmanparast insisted that "conventional military" operations were the only activities taking place in Parchin.

An interesting aspect of the ISIS report shows how off base the IAEA was during its 2005 visit to Parchin. Iran opened its floodgates to the nuclear watchdog at the time and in September of that year the IAEA said it didn't find anything. It wasn't until November 2011 that the IAEA said it obtained satellite images showing that Iran was conducting high-explosive tests with components necessary for a nuclear bomb. Below, you can see how far apart the area the IAEA visited is from the site that ISIS says shows signs of high-explosive tests.