From the Upper Thornhill Estates by Fernbrook Homes:

Welcome to a new definition of luxury living in a spectacular natural setting. Upper Thornhill Estates is a fine community of estate lots nestled in a prime greenbelt location at Dufferin and Major Mackenzie. Most lots back on to gorgeous ravines and conservation lands, offering residents a serene connection with pristine nature. The magnificent homes are designed with elegance and graced with fine features and finishes. Though tucked away in an idyllic setting, Upper Thornhill Estates is just minutes from a wide range of amenities.