Some people like to live downtown. Others prefer the open spaces of the suburbs. But if you live in between the two, you are in the outskirts, the place where the city ends and the suburbs begin.
Outskirts describes the outer edge of a city or town, farthest from the center but still technically part of that place. If you had a city map, you could draw a line on all sides where crowded streets filled with apartment building and businesses begin to give way to single-family houses and country roads. You might not get a perfect circle but you will see that outskirts are those border places between the city and the little towns that surround it.