Complex sentence: The original plan was for a line that terminated at a new ferry and fishing port at Roshven, but landowners to the north and west of Fort William opposed the railway, arguing that it would adversely affect the deer.
Split into simpler sentences: The original plan was for a line that terminated at a new ferry and fishing port at Roshven. However, landowners to the north and west of Fort William opposed the railway, arguing that it would adversely affect the deer.