32-year-old Erik Weihenmayer from Boulder, Colorado, became the first blind person to reach the summit of Mount Everest.
15 die in the Columbine High School massacre.
JonBenét Ramsey was found dead.
Mexican grill chain Chipotle opened its first restaurant.
Ted Bundy escaped from jail.
A bomb hidden in checked luggage of United Airlines Flight 629 exploded over Longmont, Colorado killing all 44 people on board.
Mike the Headless Chicken lost his head.
Colorado became the birthplace of the cheeseburger.
The Eden train wreck happened when a trail derailed from Denver, Colorado, to St Louis, Missouri.
Colorado became the second US state to give women the right to vote.
Colorado became the 38th state to join the United States of America.
