CDMX rewards a thin wallet better than almost any capital: hundreds of murals hang in government buildings that charge nothing, a full market lunch runs 70 pesos, and the metro moves 21 million people for 5 pesos a ride.
Alberto Kalach's 2006 'megabiblioteca' hangs 250,000 books on suspended steel shelves above a whale skeleton reworked by Gabriel Orozco. Free entry, daily 08:30–19:30, plus a 26,000 m² botanical garden out the back.
Rivera covered two courtyards of the education ministry with 235 fresco panels between 1923 and 1928 — the corn festival, the Day of the Dead, the arsenal. Free, weekdays 10:00–18:00, photo ID required at the gate.
The 1907 main post office by Adamo Boari: Italian Renaissance marble, a wrought-iron double staircase cast in Florence, and gilt bronze counters still selling stamps. Free to walk in, 08:00–19:30 weekdays, 09:00–16:00 Saturday.
Around 40 mariachi groups tune up here from late afternoon. Listening from the plaza benches costs nothing; you only pay if you request a song, roughly 150–250 pesos. Busiest and best-policed Thursday to Saturday evenings.
Roughly 5,000 stalls across five buildings make this the largest retail food market in the Americas. Kilo-priced fruit, chapulines by the scoop, and fondas serving comida corrida — soup, main, rice, agua fresca — for 60–80 pesos.
A four-metre stall on Bolívar open 24 hours, cooking suadero, longaniza, tripa and cabeza in one bubbling copper vat. Tacos are 20–25 pesos each, so four plus a Boing lands under 120 pesos. Standing room only, cash only.
Roma Sur's market leans Caribbean and South American: Cuban, Colombian and Venezuelan counters selling arepas from 40 pesos, mole paste by weight, and cheap whole fish. Open daily 07:00–19:00, most stalls take cash only.
A 1912 pulquería on Aranda repainted floor to ceiling in psychedelic Aztec murals, serving fermented maguey sap from litre jars — natural, or curado with oats, guava, celery. Half a litre runs 35–45 pesos. Closed Sunday.
The longest urban cable-car line on earth: 10.6 km gliding over Iztapalapa's painted rooftops, about 40 minutes each way, for 7 pesos paid with the same Movilidad Integrada card as the metro. Runs from 05:00 on weekdays.
The hill where the Mexica lit the New Fire every 52 years is now a free 1,100-hectare national park. A 40-minute climb through pine and eucalyptus reaches the summit pyramid platform and a full panorama across the valley.
Flat-bottomed trajineras cost around 600 pesos an hour for the entire boat whatever the headcount, so six people pay 100 each. Nativitas is the least touristy of the nine docks, and canoes paddle up selling quesadillas for 30 pesos.
Coyoacán's twin plazas cost nothing after dark — the coyote fountain, buskers under the laurel trees, and five minutes south the 16th-century Capilla de la Concepción, among the oldest chapels in the Americas, on a cobbled square.