Kenneth Arnold makes the first widely reported UFO sighting near Mount Rainier, Washington.

Kenneth Albert Arnold was an American aviator, businessman, and politician.

On June 24, 1947, the private pilot Kenneth Arnold saw what he described as a string of nine shiny unidentified flying objects flying past Mount Rainier at speeds that he estimated to be at least 1,200 miles per hour (1,900 km/h).

Mount Rainier, also known as Tahoma, is a large active stratovolcano in the Cascade Range of the Pacific Northwest in the United States. The mountain is located in Mount Rainier National Park about 59 miles (95 km) south-southeast of Seattle. With an officially recognized summit elevation of 14,410 ft (4,392 m) at the Columbia Crest, it is the highest mountain in the U.S. state of Washington, the most topographically prominent mountain in the contiguous United States, and the tallest in the Cascade Volcanic Arc.

Washington, officially the State of Washington, is a state in the Pacific Northwest region of the United States. It is often referred to as Washington State to distinguish it from the national capital, both named after George Washington. Washington borders the Pacific Ocean to the west, Oregon to the south, Idaho to the east, and shares an international border with the Canadian province of British Columbia to the north. Olympia is the state capital, and the most populous city is Seattle.