Killarney Provincial Park boasts one of the oldest mountain ranges in the world. Commonly known as the La Cloche Mountains, the ridges are composed of ancient white quartzite and date back three and a half billion years. The La Cloche hills were originally taller than the

Rocky Mountains and now form some of Ontario's tallest peaks.
They are some of the oldest mountains in the Canadian wilderness. Coexisting side-by-side with the quartzite ridges are sloping red granite rocks that emerged 1.5 billion years after the quartzite. These beautiful formations make up most of the shoreline along Georgian Bay and the inland lakes of the Park.