"The Hidden City" is a concept that appears in many cultures, but the most famous historical "hidden city" of Machu Picchu was created by the Inca Emperor Pachacuti around 1450 AD. It was built as a royal estate and a religious retreat, hidden high in the Andes Mountains of Peru. It earned the name "The Hidden City" because it was never found by the Spanish Conquistadors and remained unknown to the outside world until it was "re-discovered" by Hiram Bingham in 1911. Architecturally, it is a masterpiece of "ashlar" masonry, where stones are cut so precisely that they fit together without mortar. In a modern, metaphorical sense, the term "Hidden City" is often associated with the website Skiplagged, founded by Aktarer Zaman. He "created" a way for travelers to find "hidden city" flight deals, which sparked massive legal battles with major airlines. Whether referring to ancient ruins or modern travel hacks, both "creators" changed how the world perceives the "hidden" aspects of our geography.