​There are some mysterious marks which some call airports near the ancient city of Dunhuang in Gansu Province, I believe. 
I will provide solid evidence that these are nothing like an airport that I have ever heard of and I am a retired engineering manager and a pilot.
If one goes to Google earth an enters the latitude and longitude provided on the bottom of the first image, you can move the cursor around and see that the marks are not built up in elevation as an airport would be.
Road graders and compactors are needed to pack a field sufficiently to safely take the extreme pressure that landing gears make at times. Any yielding of the dirt would cause the plane to spin out of control. Of course, there are no support buildings or taxiways to parking areas.

​One may also see that common truck traffic has made tracks out across a number of the marks and therefore it cannot be paved or a prepared surface.
If the marks were graded and compacted, they would be nearly perfectly level lengthwise and side to side. When tracing the contour with GE they still show the general contour of the area around them.
Water erosion on the west mark indicates that this desert area was once quite a bit moister and the marks were already there during heavy rains or snow runoff.
Even the darker colored areas which one might be tempted to think are paved show signs of erosion.

​P.S. Ancient or Modern?
This mysterious “grid” was discovered in China (see Google Earth coordinates on the pictures).
It is 31km x 31 km. When was it made and for what purpose?
Not far (NW) from the above location we find another grid (erosion suggests it was made very long ago – perhaps in ancient times?)

​More grids nearby:

​Mysterious Nazca-like Site near Dunhuang in China
Dunhuang is a city (pop. 187,578 (2000) in Jiuquan, Gansu province, China. It was a major stop on the ancient Silk Road. It was also known at times as Shachou, or ‘City of Sands’.
It is situated in a rich oasis containing Crescent Lake and Mingsha Shan, “Echoing-Sand Mountain”. Mingsha Shan is so named for the sound of the wind whipping off the dunes, the singing sand phenomenon.
It commands a very strategic position at the crossroads of the ancient Southern Silk Route and the main road leading from India via Lhasa to Mongolia and Southern Siberia, as well as controlling the entrance to the narrow Gansu Corridor which led straight to the heart of the north Chinese plains and the ancient capitals of Chang’an (today known as Xi’an) and Luoyang.

​Mysterious Nazca-like site is located 100 km W from Dunhuang, Jiuquan, Gansu, China.  Google Earth satellite photos show few areas with strange geometric patterns (geoglyphs).  There are also 2 areas which look like “landing strips”.
Perhaps it is a military installation, however most of the strange areas are difficult to interpret. Noticeable erosion indicates that some of the patterns could be ancient.

​Here are few Google Earth images of the most interesting areas:

​Here are coordinates for Google Earth:
Latitude:     40°28’43.07″N
Longitude:  93°28’36.42″E

​An Oopart (out of place artifact) is a term applied to dozens of prehistoric objects found in various places around the world that, given their level of technology, are completely at odds with their determined age based on physical, chemical, and/or geological evidence.
Ooparts often are frustrating to conventional scientists and a delight to adventurous investigators and individuals interested in alternative scientific theories.
In 1991, the appearance of extremely tiny, coil-shaped artifacts found near the banks of Russia’s Kozhim, Narada, and Balbanyu rivers brought about a debate that has continued to this day. These mysterious and minuscule structures suggest that there may have been a culture capable of developing nanotechnology 300,000 years ago.

​These manufactured coils were initially discovered during geological research associated with the extraction of gold in the Ural mountains. These pieces include coils, spirals, shafts, and other unidentified components.

​According to an analysis from the Russian Academy of Sciences in Syktyvkar, the largest pieces found are mostly copper, while the smallest are made of tungsten and molybdenum.
While the largest of these objects measure 1.18 inches, the smallest are only 1/10,000th of an inch, and many exhibit Golden Mean proportions. Their shape suggests that they are manufactured and not naturally occurring metal fragments. In fact, they have been found to closely resemble the same miniature components of contemporary nanotechnology.

A magnified image of one of the nano coils found in the Ural Mountains. Photo credit: Mysteries of the World, Herbert Genzmer and Ulrich Hellenbrand
Though some have asserted that these tiny structures are merely debris left behind from test rockets being launched from nearby Plesetsk space station, a report from the Moscow Institute determined that they are far too old to have come from modern manufacturing.
In 1996, Dr. E.W. Matvejeva, from the Central Scientific Research Department of Geology and Exploitation of Precious Metals in Moscow, writes that, despite being thousands of years old, the components are of a technological origin.
The pieces were found at a depth between 10 and 40 feet, in a geological stratus between 20,000 and 318,000 years old.
How were humans able to manufacture such tiny components in the distant past, and what were they used for? Some believe that the coils prove the human species enjoyed a sophisticated level of technology in the Pleistocene era, while others assert that the findings are the work of extra-terrestrials.
The artifacts have been studied at four different facilities in Helsinki, St. Petersburg, and Moscow. However, further research into these tiny structures seems to have ended in 1999 with the death of Dr. Johannes Fiebag, a principal researcher of the find.

An archaeologist believes that there’s a MASSIVE 900-meter tall pyramid hidden in plain sight beneath thick layers of vegetation and soil in Australia.
The structure is believed to date back some 5,000 years.
Pyramids are scattered all across the globe. No matter where we look, ancient cultures built marvelous ancient structures across the planet, with the most notorious monument being the Great Pyramid of Giza, an ancient wonder of engineering still standing today after thousands of years.
Now, a group of amateur archaeologists from Australia claims that before Australia was visited by the Europeans — in fact, thousands of years before that, I might add — the ancient Egyptians visited the mainland of Australia and even built Pyramids there.

​As outrageous as this may sound to many, according to the group of researchers, more than 5000 years after ancient Egyptians made their way to Australia, it is believed that a Pyramid built under a mountain in North Queensland has been discovered.
The group claims how ‘Walsh’s Pyramid’, located some 30 minutes west of the popular Australian coastal city, stands a staggering 922 meters in height.
The Pyramid is said to be the final resting place of Egyptian Royal Lord Nefer-ti-ru, according to the group.
And exactly where most people see only a massive Pyramid-shaped hill is where the vivid group of archaeologists sees more than what initially meets the eye.

​Evidence of their claims is supported by the curious “Gosford Glyphs,” a set of strange carvings that according to many researchers are Egyptian in nature.
Located in the vicinity of Sydney, the intricate carvings are believed to be thousands of years old, and were carved by ancient Egyptian sailors when they discovered the Australian continent, some 5,000 years ago.

​These curious set of hieroglyphs referred to as the Kariong Hieroglyphs due to the fact they are located in the Brisbane Water National Park, Kariong, and also called the Gosford Glyphs due to the nearby community of Gosford can be seen in New South Wales.
But countless controversies surround the alleged hieroglyphs.
Numerous archaeologists have made it clear that the Gosford Glyphs are nothing more than a modern forgery, and how it’s IMPOSSIBLE that the ancient Egyptians made their way to Australia and carved the curious set of symbols on the side of a massive rock, let alone build pyramids.
As we wrote previously, is said that amateur archaeologist Ray Johnson supposedly translated the alleged glyphs for the Museum of Antiquities in Cairo and was successful in documenting and translating the two facing walls of Egyptian characters.
The translation of the Gosford Glyphs supposedly records the story of a tragic saga of ancient Egyptian explorers that shipwrecked in a strange and hostile land — now known as Australia.
Anyway, returning back to the Pyramid in Australia, Ray Johnson is convinced how the enigmatic set of hieroglyphs at Gosford undoubtedly point how Lord Nefer-ti-ru, a former member of the ancient Egyptian Royal Family is buried at the site.
Furthermore, Johnson is convinced how the Gosford Glyphs tell the story of how ancient Egyptian sailors built TWO Pyramids in Australia, one of which was said to be found at Gympie, in central Queensland.

​It was eventually demolished leaving the whereabouts of the other Pyramid an enigma all until now.
Mr. Johnson believes that the second Pyramid is in fact located beneath thick layers of soil, hidden away from sight, remaining unperceived for thousands of years.
Despite the fact that the “hieroglyphs” point to the existence of a Pyramid located in the Area, the site in question — located at the Wooroonooran National Park — has never been researched.
This is mostly due to the fact that experts consider the location where Johnson believes the Pyramid is located a Natural granite peak.
However, archaeologists are convinced that this pyramid could be similar to the one discovered buried beneath thick layers of soil and vegetation in Visoko, Bosnia and Herzegovina.
However, mainstream scholars reject the notion there’s a Pyramid in Australia — let alone two — and that the mountain where said structure is supposedly located, only ‘appears to be the shape of a pyramidal structure’.