Grand Canyon National Park reports a 67-year-old man's death on South Kaibab Trail amid sweltering temperatures, despite CPR attempts by passersby and park medical personnel.

The NPS recommends avoiding hiking the Grand Canyon's inner trails between 10 a.m. and 4 p.m., when temperatures are at their peak. Temperatures in the inner canyon can reach over 120 degrees Fahrenheit in the shade, creating "extremely hazardous conditions for hikers," the NPS said.

A hiker has died on the South Kaibab Trail in the Grand Canyon National Park while attempting to reach the Colorado River.