It's fiction, but it has a ton of historical elements to it. The book was very well researched.
I was a history major in college and a lot of the subjects that Dan Brown touches upon in The Da Vinci Code were topics I either studied or wrote papers on.
It's a mystery/thriller novel. Sort of like a modern Indian Jones. I just figured a lot of people on here would like the book.
Here's a brief review from Amazon.com:
"A murder in the silent after-hour halls of the Louvre museum reveals a sinister plot to uncover a secret that has been protected by a clandestine society since the days of Christ. The victim is a high-ranking agent of this ancient society who, in the moments before his death, manages to leave gruesome clues at the scene that only his granddaughter, noted cryptographer Sophie Neveu, and Robert Langdon, a famed symbologist, can untangle. The duo become both suspects and detectives searching for not only Neveu's father's murderer but also the stunning secret of the ages he was charged to protect. Mere steps ahead of the authorities and the deadly competition, the mystery leads Neveu and Langdon on a breathless flight through France, England, and history itself. Brown (Angels and Demons) has created a page-turning thriller that also provides an amazing interpretation of Western history. Brown's hero and heroine embark on a lofty and intriguing exploration of some of Western culture's greatest mysteries--from the nature of the Mona Lisa's smile to the secret of the Holy Grail. Though some will quibble with the veracity of Brown's conjectures, therein lies the fun. The Da Vinci Code is an enthralling read that provides rich food for thought. --Jeremy Pugh"