Bureau of Consular Affairs-International travel information, passports, visas.
Bureau of Transportation Statistics-Statistics on travel and transportation including: National Household Travel Survey, Airlines & Airports, and Passenger Travel.
CDC Traveler's Health-Information for travelers on vaccines, medications, and other measures necessary to prevent illness and injury during international travel.
National Park Service-Manages the parks of the National Park System, the National Register of Historic Places, National Heritage Areas, National Wild and Scenic Rivers, National Historic Landmarks, and National Trails.
Airlines for America-Facts, figures, news and articles related to the air transport industry. Includes data on the airline industry, regulations, individual airports and air carriers. Some content is for members only.
Fodor’s Travel Service- Web site for the popular travel book series, this site offers free information on hotels, restaurants, destinations, and cruises.
World Travel & Tourism Council- This site deals with international travel and tourism. Information is provided for professionals, researchers and consumers. The site provides access to travel and tourism market research reports and lots of specific reports for various countries.
Full profiles provide a guide to history, politics and economic background of countries and territories, and background on key institutions. Also includes audio and video clips from BBC archives.
The CIA's World Factbook provides information on the history, people, government, economy, geography, communications, transportation, military, and transnational issues for 267 world entities.