Learn about Colonial America's most important political city and the founding of the nation by exploring some of the 20 city blocks that comprise Independence National Historical Park. While a walk along its cobblestoned streets reveals dozens of the colonies' first institutions of education, religion, culture and service, if you're in a rush head straight to Independence Mall, which houses the Liberty Bell Center and Independence Hall, where the founding fathers debated and signed the U.S. Constitution. If you've got a little more time, stroll through Independence Square, where the Declaration of Independence was read publicly for the first time, and be sure to tour Ben Franklin's post office and printing shop. Start at Independence Visitors Center for a reference point and required timed tickets to some of the (free) attractions.