In 1988. Pennsylvania designated the restored U.S. Brig Niagara as the state's official flagship. Niagara was Commodore Oliver Hazard Perry's two-masted flagship, pivotal in the naval battle of Lake Erie to regain control of the upper Great Lakes from the British during The War of 1812.

As an ambassador of the city of Erie and the state of Pennsylvania, the US Brig Niagara visits ports on the Great Lakes and the Atlantic Seaboard, giving people an opportunity to share in this unique piece of history. The United States Brig Niagara is listed on the National Register of Historic Places.

Source:

U.S. Brig Niagara: Historic Naval Ships Visitors Guide
U.S. Brig Niagara: Erie Maritime Museum
State Symbols: Hello Pennsylvania

Links:

Pennsylvania - Symbols: PA Historical & Museum Comm.
Cultural Symbols - 50 states