2 Best Sights in Buenos Aires, Argentina

All of Buenos Aires' history is packed into this unusual house. The street it's on was once a small river—the zanjón, or gorge, of the property's name—where the first, unsuccessful attempt to found Buenos Aires took place in 1536. When the property's current owner decided to develop it, he discovered all sorts of things below: pottery and cutlery, the foundations of past constructions, and a 500-foot network of tunnels that has taken over 25 years to excavate. With the help of historians and architects, they've now been restored, and the entire site has been transformed into a private museum that's valuable urban archeology. Excellent 50-minute-long guided tours in English Monday through Friday and Sunday at 12 pm, 2 pm, and 4 pm take you through low-lighted sections of the tunnels. Expect few visitors and plenty of atmosphere on weekdays; you can also visit next-door property Casa Mínima (guided visit 14,000 pesos).

Hard-core tango fans must visit the home of tango's greatest hero, Carlos Gardel. The front rooms of this once-crumbling casa chorizo (sausage house—that is, a long, narrow house) contain extensive displays of Gardel paraphernalia—LPs, photos, and old posters. The maestro's greatest hits play in the background. The back of the house has been restored with the aim of re-creating as closely as possible the way the house would have looked when Gardel and his mother lived here, right down to the placement of birdcages on the patio. Concise but informative texts in Spanish and English talk you through the rooms and the history of tango in general. Guided visits are available in Spanish Wednesdays and Fridays at 12 and 4, and on weekends at 12, 2, 4 and 6. English tours are usually available on request on weekdays.