1. March 21, 1843 - Massachusetts First Interstate Railroad Line

On March 21, 1843, the Boston and Worcester Railroad completed the first interstate railroad line in the United States, connecting Boston, Massachusetts to Worcester, Massachusetts. This new form of transportation opened up new opportunities for commerce and travel, drastically changing the way people interacted and communicated across the country.

2. March 21, 1851 - The Great Fire of Boston

On March 21, 1851, a catastrophic fire destroyed a significant portion of downtown Boston, Massachusetts. The fire lasted 12 hours and consumed over 160 homes and businesses, causing damages estimated at over $10 million dollars. Although the fire was devastating, it led to new building codes and fire-fighting techniques, ultimately improving public safety and the city's infrastructure.

3. March 21, 1901 - Massachusetts Institute of Technology Fire

On March 21, 1901, a massive fire broke out in Boston's Back Bay neighborhood, severely damaging the Massachusetts Institute of Technology (MIT) campus. Though no one was injured, several research labs were destroyed, resulting in significant financial loss and undermining the school's research efforts. The rebuilding and recovery of MIT continued, however, and it remains a world-class institution today.

4. March 21, 1940 - Future US President John F. Kennedy Enrolls at Harvard Law School

On March 21, 1940, John F. Kennedy, the future 35th president of the United States, enrolled at Harvard Law School. Kennedy would go on to graduate from the prestigious institution in 1943, setting himself up for a future in politics and public service that would capture the imagination of the American people.

5. March 21, 2014 - Boston Marathon Bombing Suspect Found Guilty

On March 21, 2014, one of the suspects in the Boston Marathon bombing, Dzhokhar Tsarnaev, was found guilty on all 30 charges against him in a federal court in Massachusetts. The bombing, which occurred on April 15, 2013, killed three people and injured more than 260. The trial and sentencing became a major national story, drawing attention to issues surrounding terrorism, immigration, and justice in the United States.