1. On July 15, 1799, the first Catholic church in Baltimore, St. Mary's, was dedicated. The church was located in Fells Point and was originally built in 1770, but was destroyed by a fire in 1787 and rebuilt in 1791.

2. Thurgood Marshall, the first African American Supreme Court justice, was born on July 15, 1908, in Baltimore. Marshall was a key figure in the civil rights movement and worked as a lawyer, arguing for the desegregation of schools and other public places.

3. In 1923, the Chesapeake Bay Bridge, which connects the eastern and western shores of Maryland, was proposed on July 15. However, it would take another 34 years for construction to begin, and the bridge finally opened to traffic in 1952.

4. On July 15, 1954, a group of four young African American men tried to integrate the Glen Echo amusement park in Montgomery County, Maryland, but were turned away. The incident was one of many in the struggle to end segregation in Maryland and other states.

5. The Baltimore Orioles baseball team won their 3,000th game in franchise history on July 15, 2019, with a 9-2 victory over the Washington Nationals. The Orioles have a long and storied history in Maryland, with roots dating back to the 1890s.