León is the most populous city and municipal seat of the municipality of León in the Mexican state of Guanajuato. In the 2020 Intercensal Survey, INEGI reported 1,721,626 people living in the municipality of León, making it the fourth-most populous municipality in Mexico. The metropolitan area of León recorded a population of 2,140,094 in the 2020 state Census, making it the seventh most populous metropolitan area in Mexico. León is part of the macroregion of Bajío within the Central Mexican Plateau.
León has a strong leather industry, offering shoes, boots, belts, jackets, and other leather accessories to national and international markets. The leather industry earned its inhabitants the nickname of "green belly" because of the green tainting in the workers' bodies resulting from treating leather. Its first-class services and hotel industry make it an important commercial center in Mexico with numerous options for entertainment, gastronomy, leisure activities, arts, and recreation. It is also considered one of the most environmentally friendly cities in Mexico and has a high number of cyclists, in part because of integrating a network of bike lanes into the SIT system.