The Instituto Espacio Para la Memoria, Av. Pte. Roque Sáenz Peña 547, 4th floor (tel. 11/4342-6103 or 11/4342-7797; www.institutomemoria.org.ar) is an organization whose work entails documenting the atrocities of the 1976-82 military dictatorship to enable prosecution of those culpable, along with preserving the physical spaces associated with them. This involves tracking documents, recording interviews, locating missing children from among the 30,000 desaparecidos, or the disappeared, along with the gruesome task of exhuming bodies and other evidence, some of which continues to be done within the heart of Buenos Aires. Among the most easily seen torture and detainment sites in Buenos Aires is the Club Atlético, or Athletic Club, which is in the Microcentro, under the 25 de Mayo highway overpass at the juncture of Paseo Colón. (You might pass it many times during your trip without knowing it is there.) The building was demolished in the late 1970s when the highway was constructed, but the underground rooms, used as torture chambers and prison cells, remain. Local area residents have outlined an angel form in the ground above as a folk memorial to those who died here. The area is fenced off while archaeological and evidence-gathering work proceeds, but is visible and periodically open for visits. A monument to the disappeared is across the street from the site. In addition, the Institute has been involved in ESMA (the Escuela Superior de Mecánica de la Armada, or Navy School), located near Newberry airport, though various groups, including the Madres de Plaza de Mayo, maintain portions of the site, allowing access on an appointment basis. This massive complex contained areas where political prisoners were detained and tortured, some of whom were then dumped into the Río de la Plata from airplanes. While these sites are not always easy to visit beyond looking through fences, they are important for understanding Argentina, and are a visceral depiction of the wide reach of the military dictatorship in its ability to terrorize the local population.