1. On March 23, 1775, the Massachusetts Provincial Congress voted to arm and equip the militia, leading to the famous battles of Lexington and Concord just over a month later.

2. Harvard University, one of the oldest and most prestigious universities in the United States, was founded in Cambridge, Massachusetts on March 23, 1636.

3. On March 23, 1857, the first passenger elevator in the United States was installed in the Haughwout Building in New York City. Although not specifically a Massachusetts event, the invention of the elevator significantly impacted the way buildings were designed and enabled the construction of taller and more complex structures, including skyscrapers in Massachusetts cities like Boston.

4. In 1954, the USS Nautilus, the first nuclear-powered submarine, was commissioned by the United States Navy in Groton, Connecticut. The Nautilus was built and tested at the General Dynamics Electric Boat division in nearby Quincy, Massachusetts.

5. On March 23, 1918, the Massachusetts State House, located in Boston, was completed after 11 years of construction. The iconic landmark is known for its distinctive golden dome, which was originally made of wood and covered in copper until it was gilded with gold leaf in 1874.