1. Colorado was granted statehood on March 21, 1876: On this day, President Ulysses S. Grant signed a bill declaring Colorado as the 38th state of the United States.

2. Colorado experienced its deadliest avalanche on March 21, 1913: Known as the "White Friday" disaster, a series of avalanches occurred in the Rocky Mountains, killing 96 people and causing significant damage to railway lines and infrastructure.

3. The Denver Art Museum opened its doors on March 21, 1971: The museum was founded in 1893 and has since become a renowned cultural institution, housing over 70,000 works of art.

4. The Colorado Avalanche won their first Stanley Cup on March 21, 1996: The team, first established in 1972, defeated the Florida Panthers in a four-game sweep to claim the championship.

5. The Colorado legislature passed a landmark gun-control bill on March 21, 2013: The bill, signed into law by Governor John Hickenlooper, expanded background checks for gun buyers and limited high-capacity magazines. The legislation sparked intense debate and political backlash from gun rights advocates.