From Linda Moulton Howe's Earthfiles.com
A retired U. S. Army Counterintelligence agent, Doug Mutschler, says that when China
exploded its largest underground nuclear test on May 22, 1992, geologists and
seismologists used the event to study the Earth's crust and discovered a large
pyramid-shaped structure underground in western Alaska between Mount McKinley
(red circle north of Anchorage) and Nome on Norton Sound. Allegedly,
Anchorage Channel 13 broadcast one news story in the fall of 1992 about the
China nuclear test and subsequent pyramid discovery. The Army agent says he
learned the news report was ordered erased. This is still under investigation and
people are coming forward who till now had remained silent.
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Thus far there is no clear explanation what it is or what it is for.