Hundreds of homes destroyed by Colorado wildfire

Smoke from the Waldo Canyon fire rises above evacuated homes in Colorado Springs (Getty Images)

A raging wildfire that forced tens of thousands to flee destroyed an estimated 346 homes this week, making it the most destructive fire in the US state of Colorado's history, officials said.

Amid the devastation in the foothills of Colorado Springs, there were hopeful signs.

Flames advancing on the US Air Force Academy were stopped and cooler conditions could help slow the fire.

Colorado Springs, the state's second-largest city, is home to the US Olympic Training Centre, Norad and the Air Force Space Command, which operates military satellites. They were not threatened.

President Barack Obama was to tour fire-stricken areas today.

From above, the destruction becomes painfully clear: Rows and rows of houses were reduced to smouldering ashes even as some homes just feet away survived largely intact.

On one street, all but three houses had burned to their foundations, said Ryan Schneider, whose home is still standing in a neighbourhood where 51 others were destroyed.

"I was real happy at first. My wife was happy," he said. "The emotion of seeing the other homes, though, was instant sadness."

The aerial photos showing the scope of one of the worst fires to hit the American West in decades did little to help ease the concerns of many residents who still did not know the fate of homes.