Ojos de Mar is a group of 3–6 small water bodies close to the town of Tolar Grande in Argentina and an important tourist attraction there.

[11][9] The Ojos de Mar are one of the main tourist attractions of Tolar Grande[12] and are of scientific interest due to the stromatoliths that grow there;[13] stromatoliths are the oldest traces of life on the planet[14] and at least 3.4 billion years ago helped give rise to the oxygen in the atmosphere;[15] this 2009 discovery of stromatoliths at Ojos de Mar has gained media attention[2][4] and in 2011 it led to the Ojos de Mar along with Laguna Socompa where similar stromatoliths occur to be declared a protected area by the government of the Salta Province.

[4] Other tourist attractions of Tolar Grande are the volcanoes Llullaillaco and Socompa and the Cono de Arita.

[20] The Ojos de Mar display a rich assembly of microorganisms including extremophiles in their waters which have been analyzed with bioinformatics methods.

[25][26] Because of this, plants and animals are rare in these areas and extremophile microorganisms which can tolerate the extreme conditions make up much of the biota.