As an admirer of how Dan Brown uses real places and icons from history in his books, and a lifelong fan of magical, fantasy worlds (ehem, Harry Potter) I set out to write a book that blends those two. In short, a book that I'd love to read. This post is from the author's notes in the back of the book, and explains the historical icons and places and mythical creatures that I wrote into the story.
The first historic icon I used are the Cup and Rings. These have been found throughout Europe, including Atlantic Europe, Mediterranean Europe, Mexico, Brazil, Greece and India. They consist of a concave depression, no more than a few centimeters across, pecked into a rock surface and are surrounded by etched concentric circles. Sometimes a linear channel, called a gutter leads out from the middle. It is unknown what these very old carvings signify, but I have created an explanation in the story.
Sator Stones are also ancient stone carvings that are found all over the United Kingdom and Europe. This palindrome is arranged into a square:
SATOR
AREPO
TENET
OPERA
ROTAS
One interpretation of this Latin palindrome is “The sower works for mastery by turning the wheel.” The Sator pattern of letters is illustrated on the cover as well.
Banna is a Roman fort known today as Birdoswald near the west end of Hadrian’s Wall. It sits above the River Irthing. The ruins are still visible.
Hadrian’s Wall, also known as Aelian’s Wall, was started in 122 AD, took six years to build, and runs 135 kilometers or 84 miles across England. Parts of the wall are still visible.
Thor’s Cave is in the Pennine Mountains in Staffordshire, England. Excavations in 1864–1865 and 1927–1935 found human and animal remains, stone tools, pottery, amber beads, and bronze items within Thor's Cave and the adjacent Thor's Fissure Cavern. The caves are estimated to have contained the burial sites of at least seven people. Savaric and Elias visit this place.
Jenny or Gennora Greenteeth is a legendary water fairy associated with the Lancashire area. It is said that she pulls naughty children into the lakes and ponds and drowns them.
Local legends have repeated that Uther Pendragon really did try to divert the River Eden, unsuccessfully. "Let Uther Pendragon do what he can, Eden will run where Eden ran." is one of the sayings that reflects this in that area of England.
Pythagoras, a Greek who lived from 570 to 495 BC, is best known as the creator of the Pythagorean theorem. Ancient authorities note the similarities between his religious suppositions and the Oracle at Delphi. He traveled extensively, including to Egypt and India. He had extensive influence, and many people followed him. The Pythagorum, or his followers, are referred to in the title of the book and have a big part to play in the story as well.