I channeled this in 1992 (or was it 1993?) With all the controversy around ET Archeology and Artifacts the piece still seems relevant. There are also many other stories about the Mars face so consider this another version until you come across your favorite.
There is now a planet in another part of this Galaxy that is in the star system called the Pleiades. The intelligent life that is there now has been there for many millions of years. They are similar to human beings and can be recognized as similar. That is, communication on an intelligent level is possible; they move on solid ground with a gas atmosphere; and they have two legs, two hands, a torso containing internal organs and a head with a brain and connecting nervous system. As a biological organism these beings are quite similar. About 14,000,000 years ago a social political event occurred on that planet.
The inhabitants have learned to live in a balanced ecosystem, in other words, they are able to tune their energy needs with the cycles of their planet. To do this they developed very strict codes of behavior. As long as everyone follows the ecological guidelines everyone is happy. These beings have however learned to master a technology far superior to what now exists on this planet.
About 14,000,000 years ago a group of about 100,000 individuals began to experiment with and question the rules of behavior. As we have said, these rules are quite strict but they work. Breaking them can set off an ecological chain reaction similar to what is now happening on Earth. These beings were banished from the planet. They set sail in an enclosed system that could sustain them for centuries until they could find a planet suitable for habitation. The beings did not have a high tolerance to alien microorganisms so finding a planet was not that easy, also a correct gas balance needed to be found.
MARS
After about a journey of 10,000 years they discover this solar system. Earth seems too scary; too much life and too unpredictable. They find Mars to be quite tolerable and they can alter to gas content to suit their needs. They engineer colonies and they can continue their evolution in better circumstances than the cramped space colony (the moon Phobos). At first they are confined to the enclosed colonies but after some time the develop a suitable climate for themselves. After a few centuries they are able to live there quite successfully.
They brought with them their proclivity however to experiment with the rules and their simple Martian ecosystem gave way to a bio catastrophe (microbe explosion) and the Martian Civilization came to and end. For these beings there was no continuation there.
Now, here is the interesting part. These beings lived reincarnation and could remember lifetimes easily. They wanted to continue their cycles of lifetimes but they needed a planet. Earth of course has a remarkably complex ecosystem but too scary for their rather frail bodies. So, they find a creature suitable (primates) for genetic alteration and begin incarnating on this planet.
These primate beings, having bodies well adapted for the Earth, were quite fun to be in . It was quite a thrill being so strong. Word gets around the astral plane and other beings are attracted to this planet for the primate experience. We are speaking of entire cadres investigating the earth playground.
The face? The Martians were builders and built many structures on the planet. However, when they became aware of the necessity to move, they created large monuments to help them remember their first home away from home. The faces says, "you once lived here".