Ontario is a very big place with a small area of land taken up by towns and cities and the rest being mostly untamed wilderness.
What I find best about Ontario is that the 'back words' region also known as Muskoka is only 2-2.5 hours away from Toronto so many Canadians have a practise where they go 'up north' for the weekend to their cottages to relax, swim, go boating, or even have cottage parties.

Ontario has major contrast in the two seasons of Winter and Summer. In the Summer we get hot nice weather and trips to the cottage become very frequent, while in the winter the entire place is covered in snow and snowmobiling and hockey become very popular.
Snowmobiling is where we get together with friends and family on 'sleds' and go cross country through fields, over frozen lakes, and see absolutely amazing scenery. 'Back woods' diners suddenly become bustling joints if they are located on a main snowmobile trail, with dozens of sleds filling the parking lots and curbs.

In the winter everything freezes over, so shinny (aka pickup Hockey games with no equipment) on ponds, lakes, and rivers becomes really common.

Overall I would say the most interesting thing about Ontario has to be the contrast in the seasons and the second-homes we have up north in the wild woods.

Caustizer