Short answers, pulled from the story.
Tucson was founded as a Spanish military fort on the 20th of August 1775, when Hugo O'Conor authorized the construction of Presidio San Agustín del Tucsón. The site was formally transferred to the United States under the Gadsden Purchase, signed on the 8th of June 1854.
The name Tucson comes from the O'odham words Cuk Ṣon. Cuk is a stative verb meaning "be black" or "be dark", and Ṣon refers to the base or foundation of something. The name is commonly translated as "the base of the hill is black", referring to a basalt-covered hill now known as Sentinel Peak.
In 2015, UNESCO designated Tucson a world city of gastronomy under its Creative Cities Network program, making it the first American city to receive that designation. The city's food culture draws on thousands of years of agricultural history and includes distinctive dishes such as the Sonoran hot dog, the chimichanga, and Chinese Chorizo, a Sino-Mexican fusion sausage developed in local Chinese grocery stores from the 1880s onward.
The Tucson Gem and Mineral Show is the largest gem and mineral exposition in the world, held each year during the first two weeks of February. In 2010, it spanned 43 different shows across the city, and its yearly economic impact was evaluated at $120 million in 2015.
When rail service arrived on the 20th of March 1880, Mayor R. N. "Bob" Leatherwood sent telegrams announcing Tucson as an "ancient and honorable pueblo." Newspaper writers abbreviated the phrase to "A. and H. Pueblo," which eventually became "The Old Pueblo."
Tucson earned the nickname Optics Valley in 1992 after Business Week published a cover story on the Arizona Optics Industry Association. About 150 companies in the city are involved in designing and manufacturing optics and optoelectronics systems, anchored by the Steward Observatory at the University of Arizona, which is one of the few places in the world that can cast the large mirrors used in major telescopes.