Thomas Daniel Gibbs, a 35-year-old man from Freehold, N.J., last contacted his loved ones on July 22 during a trip to Grand Canyon National Park. He's been missing ever since.

A USA TODAY analysis found more than 600 fires that burned at least partly inside national parks in the past four decades.

A national park in southwest Colorado partially reopened Wednesday for the first time since a fire broke out earlier this month, while a fire at Grand Canyon National Park prompted more closures outside of the park.