32-year-old Erik Weihenmayer from Boulder, Colorado, became the first blind person to reach the summit of Mount Everest.
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Aurora shooting leaves 12 dead, 70 wounded.
Ted Bundy escaped from jail.
15 die in the Columbine High School massacre.
Colorado became the second US state to give women the right to vote.
A bomb hidden in checked luggage of United Airlines Flight 629 exploded over Longmont, Colorado killing all 44 people on board.