Other well-known central neighborhoods include Condesa, known for its Art Deco architecture and its restaurant scene; Colonia Roma, a beaux arts neighborhood and artistic and culinary hot-spot, the Zona Rosa, formerly the center of nightlife and restaurants, now reborn as the center of the LGBT and Korean-Mexican communities; and Tepito and La Lagunilla, known for their local working-class folklore and large flea markets. Santa María la Ribera and San Rafael are the latest neighborhoods of magnificent Porfiriato architecture seeing the first signs of gentrification.

West of the Historic Center (Centro Histórico) along Paseo de la Reforma are many of the city’s wealthiest neighborhoods such as Polanco, Lomas de Chapultepec, Bosques de las Lomas, Santa Fe, and (in the State of Mexico) Interlomas, which are also the city’s most important areas of class A office space, corporate headquarters, skyscrapers, and shopping malls. Nevertheless, some areas of lower-income colonias are right next to rich neighborhoods, particularly in the case of Santa Fe.

The south of the city is home to some other high-income neighborhoods such as Colonia del Valle and Jardines del Pedregal and the formerly separate colonial towns of Coyoacán, San Ángel, and San Jerónimo. Along Avenida Insurgentes from Paseo de la Reforma, near the center, south past the World Trade Center and UNAM university toward the Periférico ring road, is another important corridor of corporate office space. The far-southern boroughs of Xochimilco and Tláhuac have a significant rural population, with Milpa Alta being entirely rural.

East of the center are mostly lower-income areas with some middle-class neighborhoods such as Jardín Balbuena. Urban sprawl continues further east for many miles into the State of Mexico, including Ciudad Nezahualcoyotl, now increasingly middle class but once full of informal settlements. Such slums are still found on the eastern edges of the metropolitan area in the Chalco area.

North of the Historic Center, Azcapotzalco and Gustavo A. Madero have important industrial centers and neighborhoods that range from established middle-class colonias such as Claveria and Lindavista to huge low-income housing areas that share hillsides with adjacent municipalities in the State of Mexico. In recent years, much of northern Mexico City’s industry has moved to nearby municipalities in the State of Mexico. Northwest of Mexico City itself is Ciudad Satélite, a vast middle-class to upper-middle-class residential and business area.

The Human Development Index report of 2005 shows that there were three boroughs with a very high Human Development Index, 12 with a high HDI value (9 above .85), and one with a medium HDI value (almost high). Benito Juárez borough had the highest HDI of the country (0.9510) followed by Miguel Hidalgo, which came up fourth nationally with an HDI of (0.9189), and Coyoacán was fifth nationally, with an HDI of (0.9169). Cuajimalpa (15th), Cuauhtémoc (23rd), and Azcapotzalco (25th) also had very high values of 0.8994, 0.8922, and 0.8915, respectively.

In contrast, the boroughs of Xochimilco (172nd), Tláhuac (177th), and Iztapalapa (183rd) presented the lowest HDI values of Mexico City, with values of 0.8481, 0.8473, and 0.8464, respectively, which are still in the global high-HDI range. The only borough that did not have a high HDI was that of rural Milpa Alta, which had a “medium” HDI of 0.7984, far below those of all the other boroughs (627th nationally, the rest being in the top 200). Mexico City’s HDI for the 2005 report was 0.9012 (very high), and its 2010 value of 0.9225 (very high), or (by newer methodology) 0.8307, was Mexico’s highest.

Historically, and since Pre-Columbian times, the Valley of Anahuac has been one of the most densely populated areas in Mexico. When the Federal District was created in 1824, the urban area of Mexico City extended approximately to the area of today’s Cuauhtémoc borough. At the beginning of the 20th century, the elites began migrating to the south and west and soon the small towns of Mixcoac and San Ángel were incorporated by the growing conurbation. According to the 1921 census, 54.78% of the city’s population was considered Mestizo (Indigenous mixed with European), 22.79% considered European, and 18.74% considered Indigenous. This was the last Mexican Census which asked people to self-identify with a heritage other than Amerindian. However, the census had the particularity that, unlike racial/ethnic census in other countries, it was focused in the perception of cultural heritage rather than in a racial perception, leading to a good number of white people to identify with “Mixed heritage” due to cultural influence. In 1921, Mexico City had less than one million inhabitants.

Up to the 1990s, the Federal District was the most populous federal entity in Mexico, but since then, its population has remained stable at around 8.7 million. The growth of the city has extended beyond the limits of the city to 59 municipalities of the State of Mexico and 1 in the state of Hidalgo. With a population of approximately 19.8 million inhabitants (2008), it is one of the most populous conurbations in the world. Nonetheless, the annual rate of growth of the Metropolitan Area of Mexico City is much lower than that of other large urban agglomerations in Mexico, a phenomenon most likely attributable to the environmental policy of decentralization. The net migration rate of Mexico City from 1995 to 2000 was negative.

Representing around 18.74% of the city’s population, indigenous peoples from different areas of Mexico have migrated to the capital in search of better economic opportunities. Nahuatl, Otomi, Mixtec, Zapotec and Mazahua are the indigenous languages with the greatest number of speakers in Mexico City.