Kalakshetra Foundation, College of Fine Arts is one of the most traditional, authentic and famous Bharatanatyam institutions. And this is the place where Bharatantyam originated from. The academy was founded in January 1936 by Rukmini Devi Arundale. Under Arundale’s guidance the institution achieved national and international recognition for its unique style and perfection.
Kalakshetra literally means a holy place of arts (Sanskrit: Kala – Arts, Kshetra – Field or Holy place) and this meaning is the underlying principle of the institution, which was established, in the words of Rukmini Devi, “With the sole purpose of resuscitating in modern India recognition of the priceless artistic traditions of our country and of imparting to the young the true spirit of Art, devoid of vulgarity and commercialism.” The training of young and talented people by masters of art, with the background of a traditional and religious spirit, has been its major aim.
Here is the link to the official website of Kalakshetra.
You can read more about Kalakshetra on Wikipedia.