How this city is organised. Mexico City is divided into 16 alcaldías, or boroughs — called delegaciones until 2018, and still widely called that. Inside them are the colonias, the neighbourhoods, and this is the level at which the city makes sense.
The four that hold almost the whole visitor circuit. Cuauhtémoc — the historic centre, Roma, Condesa, Juárez and the Zona Rosa. Miguel Hidalgo — Chapultepec, Polanco and the great museums. Coyoacán — the colonial centre, the Frida Kahlo Museum, the Viveros. Álvaro Obregón — San Ángel and its Saturday bazaar.
And the ones worth the extra journey. Xochimilco for the canals and chinampas, World Heritage since 1987. Gustavo A. Madero for the Basilica of Guadalupe. Tlalpan for its colonial centre and the Ajusco. Azcapotzalco, seat of the Tepanec dominion before Tenochtitlan. And Iztapalapa, which has more original pueblos than any other borough and the Cablebus, with the best views in the city.
The practical detail that prevents trouble. Colonia names repeat across boroughs — there is more than one Guadalupe, more than one Santa María, more than one Centro. Always give the borough and postcode with an address, or you will end up on the other side of the city.