We live in a densely settled suburb, but there are rabbits and raccoons and woodchucks everywhere, and there's a family of foxes that lives in an area where a railroad line abuts a small river. Lots of dense trees. If there's proper habitat they'll come. I have surprised a fox at my cat's food bowl twice in the past six months. I've been successful in attracting two pairs of redtailed foxes for a couple of years.
Foxes are usually nocturnal and hunt only at night unless they're sick with mange.
They come about when the streets are dark and quiet. Their sense of smell is the best. When I put food out the foxes are usually here within 30 minutes. I live in an older residential area within Toronto, so you don't have to live in the bush to attract them. Beef is what I give them.