Shiloh National Military Park Boundary Adjustment and Parker's Crossroads Battlefield Designation Act - Modifies the boundary of Shiloh National Military Park to include the following areas identified on the map entitled "Shiloh National Military Park, Proposed Boundary Adjustment" and dated April 2012: (1) Fallen Timbers Battlefield, (2) Russell House Battlefield, and (3) Davis Bridge Battlefield. Authorizes the Secretary of the Interior to acquire lands by donation, purchase from willing sellers, or exchange.
Establishes Parker's Crossroads Battlefield in Tennessee, consisting of the area identified on the map entitled "Parker's Crossroads Battlefield, Proposed Boundary" and dated April 2012, as an affiliated area of the National Park System.