Born from the partnership of W. Douglas Burden, C.V. Whitney, and Count Ilia Tolstoy, Marine Studios opened in 1938. The attraction was designed for filmmakers to shoot underwater footage and give visitors an opportunity to see marine life live and up close. An estimated 20,000 visitors attended the opening of the world's first Oceanarium. During the 1940's, the attraction evolved into one of the world's leading marine research institutions. In the 1950's, with the help of trainers from the Ringling Brothers and Barnum & Bailey Circus, Marine Studios became the birthplace of dolphin training. Dolphin shows helped elevate the attraction, now called Marineland, to become one of the most popular tourist destinations in Florida. It provided scientists opportunities to study the behavior of dolphins, and led to the discovery of echolocation, also known as biosonar. Listed on the National Register of Historic Places in 1986, Marineland closed for a complete renovation in 2004. Many buildings were torn down and the attraction was converted into a dolphin conservation center in 2006. Georgia Aquarium purchased and rehabilitated the property in 2011.