Timoteo Domínguez Island

Timoteo Domínguez Island (Isla Timoteo Domínguez) is an Uruguayan island off the Río de la Plata coast of Uruguay.

The only land border between Argentina and Uruguay
The Argentine exclave Martín García island is within the boundaries of Uruguayan waters since 1973 when both countries signed the Rio de la Plata Treaty establishing Martín García as an Argentine territory to be exclusively used as a nature reserve. In 1961 river sediments gave birth to a small sand bank north of the island, within Uruguay's sovereignty, but as it naturally grew it formed into an island and then in the 1980's it finally merged with Martin García island creating the very first land border between Argentina and Uruguay: the islands Martín García and Timoteo Domínguez are united.