1. On May 30, 1879, the first railroad tunnel under the Hudson River was completed, connecting New Jersey to Manhattan. The tunnel was built by the Delaware, Lackawanna and Western Railroad and was designed by engineer S. DeWitt Bloodgood. It allowed trains to bypass the busy New York Harbor, making transportation and trade more efficient.

2. In 2011, on May 30, a powerful tornado hit the town of Springfield, New Jersey, causing extensive damage. The tornado was classified as an EF-3, with winds of up to 165 miles per hour. It destroyed homes, uprooted trees, and knocked out power to thousands of residents.

3. The first baseball game played in New Jersey under official National League rules took place on May 30, 1883. The game was between the New York Gothams (later the Giants) and the Philadelphia Phillies, and was played in Hoboken, New Jersey. The Gothams won the game 5-1.

4. On May 30, 1937, the first balloon-riding monkey was launched from South Orange, New Jersey. The monkey, named "Albert II", was sent into the stratosphere by Captain Albert W. Stevens and Dr. Allen E. Davison as part of their research on the effects of high altitude on living creatures. Unfortunately, Albert II died during the flight due to a parachute malfunction.

5. On May 30, 1783, the Treaty of Paris was signed, officially ending the American Revolutionary War. The treaty recognized the independence of the United States from Great Britain and established the boundaries of the new nation. New Jersey played a significant role in the war, with many battles and encampments taking place across the state.