A taxi to Bajío International Airport will cost about M$300 to M$350. A cheaper option is a frequent bus to Silao (M$20) and a taxi from there (M$150).
Between the bus station and city center, around-the-clock ‘Central de Autobuses’ buses run constantly. From the center, you can catch them heading west in the tunnels below Juárez (there are several entries: El Jardín, Mercado Hidalgo and Plaza Baratillo). A taxi to the bus station costs around M$30 to M$40.
City buses (M$4) run from 7am to 10pm. Taxis are plentiful in the center and charge about M$25 to M$30 for short trips around town.