Most of you, if not all, are familiar with Dan Brown's book "The Da Vinci Code". I wasn't a big fan of the book, but that can be due in part to the fact that I had previously read most of the "non-fiction" books Brown based his novel on. Most notably, "Holy Blood, Holy Grail" by Michael Baigent, Richard Leigh, and Henry Lincoln. However, one thing Brown did achieve with his "novel" is bring to the mainstream audience numerous theories in regards to Christianity that had been floating around for decades.
His book seemed to also give mainstream audiences a deeper appreciation, or perhaps a new way, of viewing the artwork of Leonardo Da Vinci.
When it comes to weird "coincidences" or "hidden" messages in artwork, Da Vinci doesn't have a corner on the market. One theory that has been making its rounds in the conspiracy/UFO circuits is that there are numerous pieces of artwork dating back as far as pre-historic cave drawings that depict UFO's.
Moving forward in history, most of this artwork centers on religious works and subject matter. I am not certain that this link exists as merely part of religious subject matter, or if it exists because the larger percentage of paintings from this period were religious in nature. After all, it was the church that had the money to commission paintings.
Regardless, when one examines these paintings closely, strange symbolic images do appear in the paintings. Are they UFO's or intended to represent UFO's by the artist? I am not certain. I am not even certain I believe in UFO's. However, I do find the study of these images somewhat interesting and a nice distraction from everyday news.
So let the speculation begin, check out the artwork on these various websites that I have come across and form your own opinions:
Ancient Artwork & Art and UFO's