Depends on what you like to do and see.
The fort might have been Fort Erie just across from Buffalo
https://www.ontariotravel.net/en/listing/Old-Fort-Erie/101159

Travelling through to London allows you to continue on to either cross at Windsor/Detroit or Sarnia/Port Huron on your way home.
there are 4 lane highways to either of those routes BUT lots of more scenic ways to follow if the time and desire suits you.

You might find more info at the Ontario tourism site and ask more questions about anything you want as there are a number of people from Ontario that can answer specific questions from things closer to them.

For instance I live close enough to Stratford to know if you are interested in Shakespeare there is a world renowned theatre there with Shakespeare plays through out the summer 

The home address for Ontario tourism is  https://www.ontariotravel.net/en/home  then you can pick the area of the province you are interested in.
You would be traveling  through the Niagara region first then southern edge of Hamilton Halton Brant region and on into Southwestern region.  The Huron Perth Waterloo Wellington region is just north of London/Woodstock on your probable route.

Happy planning and be sure to ask any specific questions you might have.