1. The United States Post Office opened on September 1, 1774, becoming the first postal service in New York and the entire United States.

2. In 1807, the Clermont, the first steamboat designed by Robert Fulton, made its maiden voyage from New York City to Albany, marking the beginning of the steamship era in New York.

3. On September 1, 1904, the first section of the New York City Subway opened, connecting City Hall in Manhattan to 145th Street in Harlem. This was a major milestone in transportation history, as it was the first subway system in the United States.

4. The tragic terrorist attacks on the World Trade Center took place on September 11, 2001; however, on September 1, 2011, the National September 11 Memorial & Museum was officially opened to the public, serving as a space for reflection and remembrance.

5. On September 1, 2019, New York became the first state to ban the sale of flavored e-cigarettes in an effort to combat youth vaping. This ban took effect on May 18, 2020, and has since been lifted due to legal challenges.