Question: Where is the river that is crossed by the Freeport Rail Bridge, located on a map?

full_context: Document 1: PC&Y Railroad Bridge: The PC&Y Railroad Bridge carries a single railroad track over the Ohio River, between Stowe Township, Allegheny County, Pennsylvania and Neville Island, Pennsylvania.
Document 2: French Creek (Allegheny River tributary): French Creek (also known as the Venango River) is a tributary of the Allegheny River in northwestern Pennsylvania and western New York in the United States.
Document 3: Pucketa Creek: Pucketa Creek is a tributary of the Allegheny River located in both Allegheny and Westmoreland counties in the U.S. state of Pennsylvania.
Document 4: Herr's Island Railroad Bridge: The Herr's Island Railroad Bridge, also known as the West Penn Railroad Bridge, is a truss bridge across the Allegheny River between the Pittsburgh neighborhoods of Troy Hill and Herrs Island (commonly referred to as Washington's Landing).
Document 5: Cheat River: The Cheat River is a tributary of the Monongahela River in eastern West Virginia and southwestern Pennsylvania in the United States. Via the Ohio River, the Cheat and Monongahela are part of the Mississippi River watershed. Owing to the ruggedness of the surrounding Allegheny Mountains, the Cheat remains largely remote with few settlements or developments along its banks. Its headwaters are in the Cheat-Potomac Ranger District of the Monongahela National Forest.
Document 6: Allegheny River: The Allegheny River (/ ˌæləˈɡeɪni / AL - ə - GAY - nee) is a principal tributary of the Ohio River; it is located in the Eastern United States. The Allegheny River joins with the Monongahela River to form the Ohio River at the ``Point ''of Point State Park in Downtown Pittsburgh, Pennsylvania. The Allegheny River is, by volume, the main headstream of the Ohio River.
Document 7: Point Pleasant Rail Bridge: The Point Pleasant Rail Bridge is a cantilever bridge that crosses the Ohio River between Gallia County, Ohio and Point Pleasant, West Virginia. At the present time, the bridge is being used by the Kanawha River Railroad for transporting goods from point to point via rail, but it was once used by Norfolk Southern, Conrail, Penn Central, and the New York Central Railroad.
Document 8: List of crossings of the Monongahela River: This is a complete list of current bridges and other crossings of the Monongahela River starting from Pittsburgh, Pennsylvania, where the river helps to form the headwaters of the Ohio River, and ending in Fairmont, West Virginia, where the West Fork River and Tygart Valley River combine to form the Monongahela.
Document 9: Cowanshannock Creek: Cowanshannock Creek (the eastern section is sometimes referred to as the North Branch Cowanshannock Creek) is a tributary of the Allegheny River in Armstrong and Indiana counties, Pennsylvania in the United States.
Document 10: Brilliant Branch Railroad Bridge: The Brilliant Branch Railroad Bridge is a truss bridge that carries Allegheny Valley Railroad's Brilliant Branch across the Allegheny River between the Pittsburgh neighborhood of Highland Park and Aspinwall, Pennsylvania.
Document 11: Freeport Rail Bridge: The Freeport Rail Bridge is a truss bridge that carries the Norfolk Southern Railway across the Allegheny River between Freeport and Allegheny Township in Pennsylvania.
Document 12: Deer Creek (Allegheny River tributary): Deer Creek is a tributary of the Allegheny River located in both Allegheny and Butler counties in the U.S. state of Pennsylvania.
Document 13: George D. Stuart Bridge: The George D. Stuart Bridge (commonly known as the Tarentum Bridge) is a steel deck truss bridge that carries vehicular traffic across the Allegheny River between New Kensington and Tarentum in the U.S. state of Pennsylvania.
Document 14: Emlenton Low Level Bridge: The Emlenton Low Level Bridge is a girder bridge that spans the Allegheny River at Emlenton in the U.S state of Pennsylvania. It connects two separate portions of the borough in Venango and Clarion counties. It replaced, an 1883 truss bridge that stood just upstream, which replaced several previous wooden structures; the modern bridge was constructed in 1987. This bridge is dwarfed by its more famous nearby cousin, the 1968 Emlenton Bridge along Interstate 80.
Document 15: 33rd Street Railroad Bridge: The 33rd Street Railroad Bridge is a truss bridge that carries the Allegheny Valley Railroad on the P&W Subdivision over the Allegheny River in downtown Pittsburgh, Pennsylvania, United States.
ground_truth: Eastern United States
sub_queries: Freeport Rail Bridge >> crosses Answer: Allegheny River
where is Allegheny River located on a map Answer: Eastern United States