The Ancient Alien Question: A New Inquiry Into The Existence, Evidence and Influence of Ancient Visitors, by Philip Coppens, poses some very important questions as to how advanced ancient engineering feats were accomplished by the ordinary people of the time. There is a considerable impossibility to recreate a number of engineering feats even utilizing modern principles of mathematics and engineering. Some of the ancient Egyptian engineering principles may be emulated to strengthen building structures in earthquake zones in the USA and elsewhere. Examples are the pyramidal structures of Giza with huge slabs that counterbalance each other — even during earth movements.
For instance, there are three 800 ton stones incorporated into the base of the Temple of Baalbek in Lebanon, while a single stone weighing more than 1200 tons lies abandoned in a nearby quarry. At the end of the twentieth century, there was equipment capable of lifting up 2000 tons, although transportation of the blocks was virtually impossible to perform. The meaning is that the engineers of Baalbek possessed a technology surpassing modern capabilities.
Out of Place in Time and Space, by Lamont Wood, explains the controversy over a 1460 painting of the Christ child holding a toy helicopter in hand while being held by the Mother Mary. The cover of the book shows a picture of the Mother Mary with a flying saucer overhead. So, the art world provides some independent evidence of unexplained phenomena centuries ago.
Another imponderable is that in 2500 BC, the three pyramids of the Giza Complex in Egypt were laid out in the formation of Orion's Belt. Two millennia afterward, the three pyramids in Teotihuacan in Mexico (the other side of the world) were constructed similarly.
A similar imponderable is life expectancy as set forth in the Bible. The Book of Genesis sets life expectancy at 120 years. Genesis, Book 5 cites Adam who lived 930 years and at least 6 other people who lived beyond 900 years old. Martin Luther believed that these patriarchs had a better diet and sounder bodies with less of an impact of sin.