Rock urbano is the Mexico City working-class-neighbourhood (barrio) strand of Mexican rock: blues-rock and hard-rock in Spanish, coarse in sound, singing about factory work, the Metro, poverty, cantinas (bars), and encounters with the police. Many songs are named for actual Mexico City locations (Tepito, Metro Balderas, La Merced). The instrumentation is standard blues-rock — guitar, bass, drums, vocal, harmonica — and the recordings are deliberately rough. Tempos run 110–140 BPM. Vocals are gravelled and often refuse to rhyme, spitting the lines out. Álex Lora's voice is the signature of the genre.

The origin point is Three Souls In My Mind (renamed El Tri in 1978), formed in Mexico City in 1968 by Álex Lora (born 1952). Their earliest gigs took place immediately after the 2 October 1968 Tlatelolco massacre, when government troops shot hundreds of protesting students during the pre-Olympics crackdown. In 1971 the outdoor festival Avándaro — 'the Mexican Woodstock' — provoked a de facto government ban on rock concerts, and the scene went underground into illegal venues called Hoyos Funky ('funky holes'). Ten-plus years underground steered rock urbano away from the polish of commercial rock. In 1978 the band renamed itself El Tri; Lora has led it continuously for fifty-plus years since. Adjacent bands include Botellita de Jerez (1983–93), who called their style 'Guacarock' and mixed lucha libre and rock parody; La Cuca (1989); La Lupita (1992). Rockdrigo González (1950–85), a folk-rock singer-songwriter killed in the September 1985 Mexico City earthquake, remains the movement's mythologised singer-songwriter figure.

Lora's voice — nasal, gravelly, technically imperfect — is the anchor. 'Metro Balderas' (1984) is a heartbreak song set on Mexico City Metro Line 1, later covered pan-Latin by Argentina's Fito Páez. Lora's pitch wanders to the edge of collapse without going over, and that unstable edge is what gives the songs their credibility as 'street music.' Botellita de Jerez's 'Charrock and Roll' is a pun on charro (cowboy) plus rock and roll, with the Mexican folk tradition and rock both being lightly mocked at the same time.

El Tri, 'Metro Balderas' (1984). Then 'Chavo de Onda' (1985), still sung in Mexico City twelve years after Lora wrote it. Rockdrigo González's 'Distante Instante' as the mythologised singer-songwriter recording. The proper environment is a Mexico City cantina on a humid night with a beer — this is not headphone music, it's music you sing along to.

Álex Lora has led El Tri for over half a century, which puts the band among the longest continuously active rock groups anywhere. In Mexico City he is recognisable enough that ordinary passers-by stop him for handshakes on the Metro platform. Rockdrigo González's death in the 19 September 1985 earthquake reportedly took most of his unreleased tapes with him — that loss is a central part of his 'Mexico's Bob Dylan' mythology.