Martín García Island

Martín García Island is a small island in the Río de la Plata estuary administered by the Buenos Aires Province of Argentina. It occupies a strategic position in the estuary and contains historic buildings and fortifications.

The island contains a compact settlement, a harbour area and remnants of military and quarantine-era infrastructure that are visible to visitors. Its shoreline and built heritage reflect successive uses as a defensive post, detention site and maritime station.

Over the 19th and 20th centuries the island served military, penal and quarantine roles for the region and has been administered by Argentina; its buildings and ruins record these varied functions. Portions of the island’s territory have also been managed for conservation and limited public access in recent decades.

Martín García Island sits in the Río de la Plata estuary, administered by Buenos Aires Province, and is located relatively close to the Uruguayan coast within the riverine boundary region.

• Access and administration: The island is Argentine territory in the Río de la Plata and lies close to the Uruguayan mainland; access is by organised boat services and visits may be limited.

What to See #

• Harbour and settlement: The island's harbour area and small settlement cluster contain historic buildings and the main point of entry for visitors arriving by boat.
• Historic fortifications and buildings: Ruined military and quarantine-era structures remain on the island and reflect its use in colonial and 19th-century Argentine maritime administration.