Complex sentence: The highway heads north through Middle Swan, intersecting the start of Toodyay Road, and the meeting point of Reid and Roe Highways, which together from Perth's ring road, signed as State Route 3.
Split into simpler sentences: The highway heads north through Middle Swan, intersecting the start of Toodyay Road after, and then the meeting point of Reid and Roe Highways after another. Those highways together from Perth's ring road, signed as State Route 3.