Grand Canyon National Park was established in 1919, when President Woodrow Wilson signed the Grand Canyon National Park Act on February 26. The law made the Arizona landmark the United States’ seventeenth national park.
The year 1919 is sometimes confused with earlier dates in the canyon’s protection history. Theodore Roosevelt designated the Grand Canyon National Monument in 1908, and the area had also been treated as a forest reserve and game preserve before receiving national park status. Those earlier designations protected the landscape but did not create Grand Canyon National Park.
The park centers on the immense gorge carved by the Colorado River in northern Arizona. Its boundaries were later expanded: in 1975, Grand Canyon National Park absorbed Grand Canyon National Monument and Marble Canyon National Monument. The park became a UNESCO World Heritage Site in 1979. Thus, 1908 marks an important preservation milestone, but 1919 is the correct year for the national park’s establishment.