YARNELL, Ariz. (AP) -- The location sits in a basin surrounded on three sides by charred, boulder-strewn mountains. Blackened cactuses appear as if they melted in the flames. Rocks the size of pickup trucks are perched precariously on the steep hillsides. An American flag flaps in the wind near a Granite Mountain Hotshots T-shirt that hangs on a burned cactus as a makeshift memorial to the men who died there.
Authorities provided a tour Tuesday of the location where 19 elite firefighters, known as Hotshots, were engulfed in flames last month while protecting a former gold rush town in Arizona from a volatile wildfire.
The site provides perspective of the terrain crew members faced as they found themselves trapped by a wall of fast-moving flames while erratic winds whipped the blaze in all directions.
Officials speculated the fire quickly shifted toward them, forcing the men to retreat into the bowl beneath the mountains, the hillsides way too steep to even attempt to outrun the flames.
"It was like a blowtorch in a tunnel," said Jim Paxon, a spokesman for the Arizona Division of Forestry, which was managing the fire around Yarnell, about 80 miles northwest of Phoenix. "The fire's rate of speed and intensity was beyond comprehension."
Prescott Wildland Fire Chief Darrell Willis, who helped form the Hotshots crew, said it appeared the men quickly tried to clear the area of scrub and brush that could fuel the fire, using hatchets, chain saws and shovels, hoping they could endure the intense heat as the blaze bore down.
They deployed their emergency shelters, but the heat was too much. All 19 died at the scene. The 20th crew member, who was serving as a lookout, was the only survivor.
The blaze ended up destroying more than 100 homes before it was fully contained on July 10.
The fire began with a lightning strike on Friday, June 28, and worsened by the hour through the weekend - at one point causing flames up to 20 feet high. The Granite Mountain Hotshot crew was called in on the morning of June 30 to help protect the town of Yarnell in the foothills south of Prescott.
Afternoon thunderstorms and associated winds of more than 50 mph whipped the fire into an inferno as 19 of the Hotshots climbed over a ridge.
They likely saw the fire advancing on a nearby ranch, and were headed there to save the structure when the blaze suddenly turned toward them, Willis said. The fire forced them to retreat to the relatively flat area surrounded by mountains where they found themselves trapped, he said, adding that he lost "19 adopted sons" on that fateful day.
"The heat was so intense their shelters broke down," Willis said as he stood on the edge of the site, now encircled by a chain link fence.
A ranch that was to serve as the Hotshots safety zone could be seen about 500 yards in the distance. Willis said the fire hooked around the men, blocking their way out of the fire's path and backing them up to the mountains.
"They protected themselves as a last resort," he said. "I don't think they were aware of how quick" the fire was moving.
"This is the most extreme fire behavior I have ever witnessed," Willis added. "I'm sickened. I'm saddened."
A national team of investigators has finished gathering evidence from the scene and interviewing other firefighters. It's expected their report on the fatalities will be completed sometime in late August or early September.
"There are a lot of whys, whats and what-ifs that you just have to realize we can't answer," Paxon said. "Those answers died with the crew."
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