Grand Canyon National Park
With more than 5 million visitors a year, the Grand Canyon has some noisier areas, particularly the South Rim, which is popular for its dramatic views of the Colorado River. But within the national park's nearly 2 million square miles, there are silent spots with noise levels as low as 18 to 23 dBA, according to the National Park Service.
One quiet nook is Havasu Canyon — it's 2,400 feet below the rim and home to the 600-member Havasupai tribe, who have lived on the canyon floor since 1882, according to the Minnesota Star Tribune. The nearest town is an eight-mile, four-hour hike up the canyon, followed by a two-hour drive. Only 20,000 people venture here each year, the Star Tribune reports.