1. Maryland became the seventh state to ratify the U.S. Constitution on March 18, 1788. This historic event cemented Maryland's place in the formation of the United States and helped establish the principles of democracy that are still in place today.

2. The first successful tobacco plantation in Maryland was established on March 18, 1634. This helped to shape the economic and cultural landscape of the state, and tobacco remains an important industry in Maryland to this day.

3. On March 18, 1965, the first contract for the construction of the Chesapeake Bay Bridge-Tunnel was awarded. This groundbreaking engineering feat connects Virginia's Eastern Shore with Virginia Beach and has become an iconic landmark in the region.

4. Maryland's first female governor, Parris Glendening, was inaugurated on March 18, 1995. During his tenure, Glendening was instrumental in the expansion of public transportation and the preservation of natural resources in the state.

5. The founding of Johns Hopkins University on March 18, 1876, was a landmark event for both Maryland and the field of higher education in the United States. The university's reputation for excellence in research and education has made it one of the most prestigious institutions in the country.