Complex sentence: It followed the route of the Saginaw Trail, an Indian trail that linked Detroit with Pontiac, Flint, and Saginaw; with the Mackinaw Trail, the Saginaw also connected north to the Straits of Mackinac at the tip of the Lower Peninsula of Michigan.
Split into simpler sentences: It followed the route of the Saginaw Trail, an Indian trail that linked Detroit with Pontiac, Flint, and Saginaw. With the Mackinaw Trail, the Saginaw also connected north to the Straits of Mackinac at the tip of the Lower Peninsula of Michigan.