Complex sentence: Slateford Junction was a railway junction in the small town of Slateford, Pennsylvania where the existing mainline of the Lackawanna Railroad joined the new Lackawanna Cut-Off.
Split into simpler sentences: Slateford Junction was a railway junction in the small town of Slateford, Pennsylvania. The junction was the meeting point of the existing mainline of the Lackawanna Railroad and the new Lackawanna Cut-Off.