UFO hunters and alien investigators claim recent images show doorways into secret underground bases on Mars but could these also be what Dr. Norman originally wrote in the book “The Truth About Mars” about air locks and bulkheads which assist the city with its air quality perhaps besides being entrances.
“I was immediately impressed by the soft white light that seemed to come from everywhere. We were standing near the entrance of a large tube. On Mars the cities are all underground and are connected together by huge oval metal tubes from three to five hundred feet in diameter. There are monorail cars as long as our pullman trains which glide silently and very swiftly from one city to another. The bottoms of these immense tubes are used for parks, growing foodstuffs and innumerable small manufacturing plants.”
Google Earth Photo with Coordinates
Other Cube Shaped Structures:
Perhaps Another Cube-Shaped Portal – Mars Curiosity Sol 120