Getting there
An hour north, until it is not
Highway 400 is the arrival and the constraint. From Toronto, about an hour in fair traffic, longer when cottage country is emptying or filling. GO trains and buses connect Barrie with Toronto on a commuter pattern. They are useful if your hours match them and a poor assumption late at night. There is no Pearson-style rail link from a terminal to the bay.
North of the city, the roads fan toward cottage lakes, toward Collingwood and Blue Mountain to the west, and toward the Bruce if you keep going. Barrie is the gateway, not those destinations. Sleep here when the bay or the split drive is the plan. Sleep there when the hill or the harbour is the plan.