Some of Buenos Aires’s best guided tours are available through the municipal tourist office on Saturday and Sunday, often but not always with English-speaking guides. The Buenos Aires Herald’s Friday “getOut!” section and Clarín’s event section both contain listings, but the complete schedule also appears in Cultura BA, a weekly giveaway tabloid from the city government; they are also posted on the city government’s website (www.buenosaires.gov.ar). In case of rain, the tours are canceled.

For conventional tours of the capital and vicinity, including the Microcentro, Recoleta and Palermo, and San Telmo and La Boca, a frequent choice is Buenos Aires Visión (Esmeralda 356, 8th floor, tel. 011/4394-2986, www.buenosaires-vision.com.ar).

Jorge Luis Borges’s widow María Kodama leads fortnightly Borgesian tours, free of charge, sponsored by municipal tourism authorities and her own Fundación Internacional Jorge Luis Borges (Anchorena 1660, tel. 011/4822-8340); phone for schedules.

Highly recommended Eternautas (Avenida Roque Sáenz Peña 1124, 4-B, tel. 011/4384-7874 or 15/4173-1078, www.eternautas.com) is an organization of professional historians who offer inexpensive walking tours (as little as US$2) and longer half-day excursions, such as “El Otro Sur,” a fascinating three-hour bus tour (US$8 pp) through working-class southern barrios like Barracas, Nueva Pompeya, Parque Patricios, and Boedo. They also go farther afield to such places as La Plata and Luján (including the historic Estancia Los Talas) for US$27.

By its very name, Tangol (Florida 971, Local 31, tel. 011/4312-7276, www.tangol.com) combines those two porteño passions, tango and soccer (¡goooooooooooollll!) in its offerings. It also does excursions farther afield, in Buenos Aires province and elsewhere. For a commercial website, it’s surprisingly informative as well.

Travel Line Argentina (Esmeralda 770, 10th floor, Oficina B, tel. 011/4393-9000, www.travelline.com.ar) conducts specialty excursions, such as its “Evita Tour” (US$45, 4.5 hours), which takes in the CGT labor headquarters, Luna Park Stadium, the Perón and Duarte residences, and other locales associated with Evita’s meteoric career.

One unique option is Cicerones de Buenos Aires (tel. 011/4330-0800, www.cicerones.org.ar), a nonprofit that matches visitors with enthusiastic non-professional guides who can provide a resident’s perspective on the city.