Academics have defined mass tourism as travel by groups on pre-scheduled tours, usually under the organization of tourism professionals. This form of tourism developed during the second half of the 19th century in the United Kingdom and was pioneered by Thomas Cook. Cook took advantage of Europe's rapidly expanding railway network and established a company that offered affordable day trip excursions to the masses, in addition to longer holidays to Continental Europe, India, Asia and the Western Hemisphere which attracted wealthier customers. By the 1890s over 20,000 tourists per year used Thomas Cook & Son.
Choć oczywiście, w drugiej połowie XX zaczęło to postępować wykładniczo.