Parque histórico natural Vuelta de Obligado, Historical natural park in San Pedro, Argentina

Parque histórico natural Vuelta de Obligado is a municipal protected area in Obligado, north of San Pedro, Buenos Aires. Its main feature is a barranca, a steep bluff dropping directly into the Paraná River, unusual for northeastern Buenos Aires, with atypical geological forms such as arches, insular rock outcrops and caverns. Above the crest lies a high terrace, and the land slopes down toward the Los Cueros stream.

The area is linked to a military conflict in 1845 between local forces and foreign fleets over national independence. The site was preserved to document this confrontation and its importance to the nation.

The reserve protects the riverside landscape where the Battle of Vuelta de Obligado was fought on 20 November 1845, today a national historic site. Its cliffs, terraces and islands are also home to archaeological remains of Guaraní, Chaná, Cayguayán and Querandí peoples, alongside Quaternary mammal fossils.

The park is easily accessible with pathways leading to key sites, and guides are available for visitors seeking more detail. An on-site museum displays historical objects and information about the past events.

The cliffs are geologically unusual for northeastern Buenos Aires, forming natural arches, island crags and caverns. The reserve also holds archaeological remains of Guaraní, Chaná, Cayguayán and Querandí peoples, plus Quaternary mammal fossils. Large tembaterí trees grow here, now rare in the region.