Ontario is very large, so sometimes people break it into two. The two parts are called Northern Ontario and Southern Ontario. Most of the people in Ontario live in the south, and that is where the big cities are. The big cities in Southern Ontario are Toronto and the rest of the Greater Toronto Area, Ottawa and the National Capital Region, Hamilton, London, Windsor, and Sarnia. The cities in the north are smaller. In the far north of Ontario hardly any people live at all, and there are no roads or railways making it difficult to even get to those places.