<P> The establishment of Grand Teton National Park took place over a period spanning more than 50 years . Located in the northwestern region of the U.S. state of Wyoming, Grand Teton National Park is 10 miles (16 km) south of Yellowstone National Park which was established in 1872, when Wyoming, Idaho and Montana were still territories and the region was very sparsely settled . By the late 19th century, conservationists were working to provide further protection to surrounding regions, leading President Grover Cleveland to create the Teton Forest Reserve, which included a portion of northern Jackson Hole . By 1902, the reserve had been combined into the Yellowstone Forest Reserve, then was divided again in 1908 by President Theodore Roosevelt, establishing the Teton National Forest, which protected most of the Teton Range . By 1907, the U.S. Bureau of Reclamation had constructed a temporary dam at the Snake River outlet of Jackson Lake . This dam failed in 1910 and a new concrete Jackson Lake Dam replaced it by 1911 . The dam was further enlarged in 1916, raising lake waters 39 ft (12 m) as part of the Minidoka Project, designed to provide irrigation for agriculture in the state of Idaho . Though efforts to protect the Teton Range and Jackson Hole as part of an expanded Yellowstone National Park dated back to the late 19th century, proposals to construct more dams on some of the other lakes in Jackson Hole led Yellowstone National Park superintendent Horace Albright to block such efforts . Albright was originally an advocate of the expanded Yellowstone plan which was very unpopular with local residents . By the mid-1920s local sentiment had changed as a result of proposals for a new national park including only the Teton Range and six lakes at the base of the range . With the general agreement of prominent Jackson Hole residents to this plan, President Calvin Coolidge signed the executive order establishing the 96,000 - acre (39,000 ha) Grand Teton National Park on February 26, 1929 . </P> <P> The valley of Jackson Hole remained primarily in private ownership when John D. Rockefeller, Jr. and his wife visited the region in the late 1920s . Horace Albright had hoped to protect the valley of Jackson Hole north of the town of Jackson from commercial exploitation . Rockefeller agreed and through a private enterprise known as the Snake River Land Company by 1927 was buying land in Jackson Hole to be later turned over to the National Park Service . In 1930 this plan was revealed to the residents of the region and was met with strong disapproval . By 1942 John D. Rockefeller, Jr. became increasingly impatient that his land holdings in Jackson Hole might never be part of Grand Teton National Park, so he wrote the Secretary of the Interior Harold L. Ickes and informed him that he was considering selling the land to another party . Secretary Ickes recommended to President Franklin Roosevelt that the Antiquities Act (which permitted Presidents to set aside land for protection without the approval of Congress) be used to establish a National Monument in Jackson Hole . </P>

When did grand teton become a national park