1. On April 3, 1783, Maryland became the seventh state to ratify the Treaty of Paris, officially ending the American Revolution. The treaty recognized the independence of the United States and established the boundaries of the new nation.

2. In 1858, the Maryland State Agricultural Society was founded on April 3 in Baltimore. The society aimed to promote and improve agriculture in the state through education, research, and community outreach programs.

3. On April 3, 1933, Maryland became the first state to adopt a statewide sales tax. The tax was initially set at 2%, but has since been increased to 6%. The revenue generated from the tax supports state and local government programs and services.

4. Orioles Park at Camden Yards, home of the Baltimore Orioles baseball team, opened on April 3, 1992. The stadium is known for its unique retro design and has been credited with revitalizing the area surrounding it.

5. On April 3, 2007, Constellation Energy announced a merger with FPL Group, creating the largest regulated utility in the United States. The company, which operates as Exelon Corporation, provides energy services to millions of customers across the country.