However, when the natural wormhole unexpectedly collapsed, it destroyed the gate.

"In each instance, the person suddenly became completely submerged by sand when the walls of the excavation unexpectedly collapsed," they wrote.

They couldn't, and went broke trying, and the Soviet Union unexpectedly collapsed.

That led him to the more general question of how order emerges from disorder and how, in turn, the most enduring structures can unexpectedly collapse.

Until the talks unexpectedly collapsed this week, the two sides were tantalizingly close to an agreement.

In 1902, it cracked, crumbled and collapsed unexpectedly.

The table unexpectedly collapsed from their weight and Angle was rendered unconscious.

In another, a performer fell 25 feet when a prop ladder collapsed unexpectedly.

Racing wildly and collapsing unexpectedly, the cast appeared to be menaced by unseen disasters.

On December 27, 2009, a wind turbine tower unexpectedly collapsed.