Quebec City
No word of a lie, the inner walls of Vieux Quebec feel more European than many of the cities in Europe. Before there was the country of Canada, there were "Upper and Lower" British Canada. And before that, Lower Canada was New France. And at the heart of New France was the colonial city of Quebec, on the cliffs overlooking the St Lawrence. Few cities in North America can claim to be older than Quebec City, initially settled in 1535 by Jaques Cartier, and later founded by Samuel De Champlain in 1608. At a minimum, most buildings behind Quebec's fortified walls are 150-200 years old. Many, in the lower part of the city can trace their construction to the 1600s. It's absolutely amazing to see a city of this age so well preserved; easily the most complete picture of a colonial walled city you'll ever find in North America.