In celebration of International Museum Day, the Pennsylvania Historical and Museum Commission will offer a "buy one general admission, get one general admission free" deal on Sunday.

Participating PHMC sites, by region:

Philadelphia and Its Countryside: Brandywine Battlefield, Pennsbury Manor, Graeme Park, Hope Lodge and Mather Mill, and Washington Crossing Historic Park.

Pittsburgh and its Countryside: Fort Pitt Museum, Somerset Historical Center, and Old Economy Village.

The Alleghenies and her Valleys: Pennsylvania Military Museum and Joseph Priestley House.

Dutch Country Roads: The State Museum of Pennsylvania, Conrad Weiser Homestead, Railroad Museum of Pennsylvania, Ephrata Cloister, Cornwall Iron Furnace, and Landis Valley Museum.

Northeast Pennsylvania Mountains: Scranton Iron Furnaces, Eckley Miners' Village, and Pennsylvania Anthracite Heritage Museum.

Pennsylvania's Great Lakes Region: Drake Well Museum, Erie Maritime Museum, and U.S. Brig Niagara.

Pennsylvania Wilds: Pennsylvania Lumber Museum.

For more information about these sites and PHMC's Trails of History program, visit www.phmc.state.pa.us.

International Museum Day is sponsored by the International Council of Museums and has been celebrated worldwide since 1977.

The Pennsylvania Historical and Museum Commission is the commonwealth's official history agency.    - Inquirer staff