Popular Mechanics:

The official declaration of America’s independence from Britain may be dated July 4, 1776, but the story of the Thomas Jefferson’s hallowed document really begins two weeks later. On July 19, the Continental Congress ordered a scribe, Pennsylvania State House clerk Timothy Matlack, to write the words on a piece of parchment big enough for everyone to read—and with room for signatures.

Since then, the Declaration of Independence has had a fairly rough time. A forensic analysis of the document shows some rough handling, damaging displays, and even a mysterious handprint. Understanding why it looks the way that it does — much more faded and battered than the U.S. Constitution or The Bill of Rights — is a romp through the history of printing, preservation, and patriotism.

It is one of the most important documents in human history and the process of its care and preservation is fascinating.