12 Best Sights in San Telmo, Buenos Aires

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 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.

Plaza Dorrego is the heart of the Feria de San Pedro Telmo—an open-air market that stretches for more than a kilometer (0.6 mile) along Calle Defensa each Sunday. Thrust your way through the crowds to pick through antiques and curios of varying vintages as well as tango memorabilia, or watch professional tango dancers perform on the surrounding cobbled streets. The unofficial "stalls" (often just a cloth on the ground) of young craftspeople stretch several blocks up Defensa, away from the market proper. As it gets dark, the square turns into a milonga, where quick-stepping locals show you how it's done.

When they tried to shut down ultravintage Bar Británico, the whole city rallied to its defense. Rub elbows with bohemian students and wizened old-timers as you perk up with a cortado (espresso "cut" with a dash of milk) or unwind with a ginebra (ginlike spirit). The area can be sketchy, so it's best to grab a cab.

Regulars insist that the picadas (snacks such as cold cuts and bread) at Bar El Federal are some of the best in town—and you can linger over them for hours, no questions asked.

Wood-paneled, dust-festooned Bar Plaza Dorrego is right on San Telmo's main square. Sip your cafecito (espresso) or icy beer at one of its window tables for some prime people-watching, all the while shelling your pile of peanuts.

Tango musicians often perform at Bar Seddon, an otherwise quiet bar with a beautiful checkered floor and old-fashioned cash register.

Geometric abstraction is the guiding principle for both the collection and the construction of Buenos Aires' contemporary arts museum. Sharply sloped walkways connect four floors of concrete-walled galleries, creating an austere backdrop for the bright lines and shapes of local financier Aldo Rubin's private collection. Regularly changing exhibitions may include pieces by contemporary local stars like Pablo Siquier and Guillermo Kuitca.

Some 7,000 contemporary artworks make up the permanent collection at this block-long museum. Formerly the site of a tobacco company, the MAMBA retains its original exposed-brick facade and fabulous wooden doors with wrought-iron fixtures. Inside, galleries showcasing a carefully curated selection of paintings, sculptures, and new media are complemented by large temporary exhibitions of local or Latin American works as well as smaller installations. Highlights include the unusual portraits of superstar collective Grupo Mondongo, who eschew paint in favor of materials like crackers, sliced ham, and chewing gum.

What better place for the National History Museum than overlooking the spot where the city was supposedly founded? Once owned by entrepreneur and horticulturalist Gregorio Lezama, the beautiful chestnut-and-white Italianate mansion that houses it also did duty as a quarantine station during the San Telmo cholera and yellow-fever epidemics before it became a museum in 1922. Personal possessions and thoughtful explanations (in Spanish) chronicle the rise and fall of Argentina's liberator José de San Martín. Other galleries celebrate the heroes of independence and foreign forces' unsuccessful attempts to invade Argentina.

The Museo Histórico Nacional (National History Museum) sits in the shade of enormous magnolia, palm, cedar, and elm trees on the sloping hillside of Parque Lezama. Bronze statues of Greek heroes, stone urns, and an imposing fountain shipped from Paris hint at former glory. Patchy grass, cracked paths, and unpainted benches are a nod to more recent times. A monument in the northwestern corner celebrates conquistador Pedro de Mendoza, said to have founded Buenos Aires on this spot. Watching over the park are the onion-shaped domes of the Catedral Santísima Trinidad Iglesia Ortodoxa Rusa (Holy Trinity Russian Orthodox Church) immortalized by Argentine writer Ernesto Sabato in his novel Sobre Héroes y Tumbas (Of Heroes and Tombs).

Wandering through this well-preserved house affords a glimpse of life in San Telmo's golden era. Behind an elegant but narrow stone facade, the building extends deep into the block, around a series of internal courtyards. This type of elongated construction—known as a casa chorizo or "sausage house"—is typical of San Telmo. Once the private residence of the well-to-do Ezeiza family, it became a conventillo (tenement), but is now a picturesque spot for antiques and curio shopping.

During the week a handful of craftspeople and a few scruffy pigeons are the only ones enjoying the shade from the stately trees in the city's second-oldest square. Sunday couldn't be more different: scores of stalls selling antiques and collectibles move in to form the Feria de San Pedro Telmo (San Pedro Telmo Fair). Tango dancers take to the cobbles come late afternoon, as do hundreds of shoppers (mostly tourists) browsing the tango memorabilia, antique silver, brass, crystal, and Argentine curios. Note that prices are high at stalls on the square and astronomical in the shops surrounding it.

More affordable offerings—mostly handicrafts and local artists' work—are on the ever-growing web of stalls along Calle Defensa.

Be sure to look up as you wander Plaza Dorrego, as the surrounding architecture provides an overview of the influences—Spanish colonial, French classical, and ornate Italian masonry—that shaped the city in the 19th and early 20th centuries.

Pickpockets work as hard as stall owners on Sundays, so keep a firm hold on bags and purses or—wiser still—leave them at home.