Ravines are one of the wonders of Toronto. Cutting deep through the city, they are islands of natural heritage. While the city carries on above them and inevitably has its impact, the ravines still offer surprising ecological diversity. And they have much to tell about Toronto's history. Jason Ramsay-Brown has had a lifelong fascination with ravines, and he has spent years exploring them and discovering their little-known history. For the past 15...