This northerly stretch of the Don offers a chance for a good leg-stretching walk and a chance to see the river and its valley unencumbered by rail lines, expressways or concrete strait-jackets.

From Steeles to York Mills Road, the river wanders freely across its flood plain, which remains in an untended state for the entire length. This isn’t exactly wilderness, but up near the north boundary of Metropolitan Toronto it’s wild enough that on a quiet morning walk through here you can encounter fox and other wildlife.

This walk actually begins by following German Mills Creek, a tributary of the...