You can add your own John Hancock to our nation’s founding document as part of Constitution Week at the home of the only American president who was born in Iowa. Tom Walch is director of the Hoover Presidential Library in West Branch and calls the Constitution the greatest document in U.S. history.Walch says hundreds of people have already signed copies of the Constitution, all of which will be sent to National Constitution Center in Philadelphia, a new museum which tells the story of the document. It was originally signed 216 years ago yesterday (Wednesday), the oldest written constitution in history.Walch says the history of the Constitution and its signing on September 17, 1787 is a great story everyone should learn. The Hoover Presidential Library is open 9 to 5 every day of the week, located just east of Iowa City. For more information, call (319) 643-5301 or surf to “www.hoover.archives.gov”.