The first base of the United States was established in 1791 in Legionville, Pennsylvania for the 'Legion of the United States', the first post-Revolutionary War standing Army. Since then, American military forces have constantly evolved and the number of military bases has multiplicated.

Today, there are hundreds of US military bases worldwide, depending on the service branch.

An air force base usually houses one or more air force squadrons under the command of Lieutenant-Colonels. The whole base is under the command of a Colonel. The most famous of these is Andrews Air Force Base because it is home to Air Force One, the Presidential Aircraft. Air Force bases are usually the best places to see an air show!

A US Navy Base is a port housing the American Fleet. The biggest ones are Naval Base Norfolk, VA (Atlantic Fleet), Naval Base San Diego, CA (Pacific Fleet), Naval Base Yokosuka, Japan (Forward Pacific Fleet) and Naval Base Gaeta, Italy (European Fleet). The Navy also has Air Stations, for example Naval Air Station Key West, to house its aircraft squadrons when they aren't deployed at sea.

The Army and the Marines also operate many bases on the American territory as well as abroad (for example, Fort Bragg, SC, Camp Lejeune, NC, or Army Base Wiesbaden, Germany).