On this day in history, two national parks were established in the United States 10 years apart–the Grand Canyon in 1919 and the Grand Tetons in 1929.

Located in northwestern Arizona, the Grand Canyon is the product of millions of years of excavation by the mighty Colorado River. The chasm is exceptionally deep, dropping more than a mile into the earth, and is 15 miles across at its widest point.The canyon is home to more than 1,500 plant species and over 500 animal species, many of them endangered or unique to the area, and it’s steep, multi-colored walls tell the story of 2 billion years of Earth’s history.

In 1540, members of an expedition sent by the Spanish explorer Coronado became the first Europeans to discover the canyon, though because of its remoteness the area was not further explored until 300 years later. American geologist John Wesley Powell, who popularized the term “Grand Canyon” in the 1870s, became the first person to journey the entire length of the gorge in 1869. The harrowing voyage was made in four rowboats.

In January 1908, U.S. President Theodore Roosevelt designated more than 800,000 acres of the Grand Canyon a national monument; it was designated a national park under President Woodrow Wilson on February 26, 1919.

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Ten years later to the day, President Calvin Coolidge signed into law a bill passed by both houses of the U.S. Congress establishing the Grand Teton National Park in Wyoming.

Home to some of the most stunning alpine scenery in the United States, the territory in and around Grand Teton National Park also has a colorful human history. The first Anglo-American to see the saw-edged Teton peaks is believed to be John Colter. After traveling with Lewis and Clark to the Pacific, Colter left the expedition during its return trip down the Missouri in 1807 to join two fur trappers headed back into the wilderness. He spent the next three years wandering through the northern Rocky Mountains, eventually finding his way into the valley at the base of the Tetons, which would later be called Jackson Hole.

Other adventurers followed in Colter’s footsteps, including the French-Canadian trappers who gave the mountain range the bawdy name of “Grand Tetons,” meaning “big breasts” in French. For decades trappers, outlaws, traders and Indians passed through Jackson Hole, but it was not until 1887 that settlers established the first permanent habitation. The high northern valley with its short growing season was ill suited to farming, but the early settlers found it ideal for grazing cattle.

Tourists started coming to Jackson Hole not long after the first cattle ranches. Some of the ranchers supplemented their income by catering to “dudes,” eastern tenderfoots yearning to experience a little slice of the Old West in the shadow of the stunning Tetons. The tourists began to raise the first concerns about preserving the natural beauty of the region.

In 1916, Horace M. Albright, the director of the National Park Service, was the first to seriously suggest that the region be incorporated into Yellowstone National Park. The ranchers and businesses catering to tourists, however, strongly resisted the suggestion that they be pushed off their lands to make a “museum” of the Old West for eastern tourists.

Finally, after more than a decade of political maneuvering, Grand Teton National Park was created on February 26, 1929. As a concession to the ranchers and tourist operators, the park only encompassed the mountains and a narrow strip at their base. Jackson Hole itself was excluded from the park and designated merely as a scenic preserve. Albright, though, had persuaded the wealthy John D. Rockefeller to begin buying up land in the Jackson Hole area for possible future incorporation into the park.

In 1949, Rockefeller donated his land holdings in Jackson Hole to the federal government that then incorporated them into the national park. Today, Grand Teton National Park encompasses 309,993 acres. Working ranches still exist in Jackson Hole, but the local economy is increasingly dependent on services provided to tourists and the wealthy owners of vacation homes.

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