[4] He was considered by Luis Abel Orquera to have been "the principal authority on indigenous Pampean-Patagonian art.

"[6] Carlos Gradin is known for his extensive studies of Cueva de las Manos.

Gradin and his team's study of cave art in and around Cueva de las Manos formed the most important research on the site.

[2][7][8] In his studies, Gradin helped to separate the different stylistic sequences of the cave, and of rock art in Patagonia as a whole.

[8][9][10][11] The importance of his discoveries to the country's natural and cultural heritage resulted in the site being named a United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage Site in 1999.