Complex sentence: The mainline toll plaza is situated just north of the Susqehanna River Bridge in Perryville, Maryland, the southbound toll plaza had been removed in 1991, but tolls are still collected for northbound traffic at this location.
Split into simpler sentences: The mainline toll plaza is situated just north of the Susqehanna River Bridge, the southbound toll plazas had been removed in 1991. Tolls are still collected for northbound traffic at this location.