Ontario is a province of Canada. It is in the eastern half of Canada, between Manitoba and Quebec. Ontario has the most people of any province, with 13,150,000 in 2009, and is home to the biggest city in Canada, Toronto, which is also the capital of the province.
Ontario also has the second largest land area, with 1,076,395 km²; only Quebec is larger by size. (Nunavut and Northwest Territories are also larger, but are called territories and not provinces). The province has one of the longest borders with the United States and there are several border crossings including the one at Niagara Falls. Along this border are 4 large lakes called Lake Ontario, Lake Erie, Lake Huron, and Lake Superior. They each are partly in Ontario and partly in the United States, and the border runs through them, but not Lake Michigan, which is entirely in the United States. These five lakes are together are called the Great Lakes.
There are a number of symbols that represent the province of Ontario. The flag is red with the British Union Jack in the top left corner and the provincial shield is on the right hand side of the flag. The provincial bird is the loon, and the provincial flower is the trillium. It has three flower petals and it is usually white but some times is pink or purple.
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.
Much of Ontario gets lots of snow in the winter. In the summer, it can get very hot in the south parts. In some big cities, there is smog in the summer.