Here's Where US Citizens Can Travel Without A Visa
An American passport grants its holder access to nearly every country in the world. In 2012, U.S. citizens and nationals could travel to 166 countries visa-free or with visa on arrival, including most countries in Europe and South America.
But there are a few big exceptions. Americans need to get advance visas to Brazil, China, Russia, India, Vietnam and most countries on the African continent.
The map below shows exactly where a U.S. passport will let you travel.