One of America's most historic cities, Philadelphia is an ideal place to spend a weekend -- preferably a long one. Be sure to see the Liberty Bell and Independence Hall, where the Constitution and Declaration of Independence were signed; both are part of Independence National Historic Park. Philadelphia also boasts some outstanding art museums, including the Rodin Museum. The Franklin Institute Science Museum is one of many local attractions honouring the life and work of Benjamin Franklin, the city's most famous ambassador. And after digesting all that history, make sure you save room for a classic Philly cheese steak sandwich.