The cover of this May 1915 Travel magazine tempted readers to imagine themselves at Yosemite National Park in California.

As the rail system became more extensive, railroad companies became major promoters of vacation travel. This brochure, Resorts and Tours Illustrated (1905), described vacation opportunities along the Boston and Maine Railroad line.

Cities became more popular vacation destinations around the turn of the 20th century, delighting tourists with the latest modern technology, artistic and scientific curiosities, and live entertainment. Commercial sightseeing tours helped simplify attractions, districts, and landmarks for city tourists. This photograph from 1895 depicts passengers aboard an electric "Sight Seeing Automobile Coach" in Washington, D.C.

The Rapid Motor Vehicle Company of Pontiac, Michigan, produced this twelve-passenger vehicle in 1906. The bus could shuttle travelers to and from hotels and rail depots or provide local sightseeing tours. In 1908, General Motors Company began purchasing Rapid's stock. The purchases of Rapid and other commercial truck companies led to the formation of General Motors Truck Company in 1912.

This poster encouraged travelers to choose the 1939-40 New York World's Fair as a vacation destination. According to the poster, not only would you see the fair, but you would also "see the world."

Scenic highway "trails" helped motorists organize the diversity of sights encountered in various regions of the country. This travel guide described four distinct motoring "trails" in New York State, each with its "own individual charm and providing the most interesting scenery, the finest concrete and macadam roads, historical landmarks, and the most convenient and comfortable hotels and inns."

Before the 1964 Civil Rights Act, African Americans faced persistent racial discrimination when traveling. It could be difficult to find restaurants, hotels, or other amenities. The Negro Motorist Green Book, begun in 1936, became a guide for the African American traveler. This 1949 edition listed travel information that would keep the traveler "from running into difficulties [and] embarrassments," and would "make his trips more enjoyable."

For much of the 20th century, Pan American World Airways exemplified innovation in air travel. The carrier pioneered the use of wide-body jumbo jets, like the Boeing 747 featured on this postcard, in the 1970s. But rising fuel costs and difficulty establishing domestic U.S. routes strained the company in the 1980s. Pan Am ended operations in 1991.