Wondering if there really would be such an opening/hangar I (UFO Sightings Hotspot) checked Mount Adams via Google Earth and although I could not find the opening/hangar, maybe covered by snow at the time they took the images, I found a giant frozen body in the snow near the top of Mount Adams.

Also a UFO scholar and second language teacher, Scott C. Waring, presented photos on his website, claiming that these are evidence of an entry to an alien base on the Mount Adams side of Washington, USA.

For many years Mount Adams has been the focus of many UFO enthusiasts, and people from all over the world go there to see bright orbs that appear in the sky most of the night. These frequent sightings have led people to infer that perhaps this mountain is home to a huge alien base.

Also, James Gilliland, owner of the ECETI farm, claims to have been invited to board an alien ship.