Québec City's stone fortification walls are 4.6 kilometres long, built and rebuilt between 1690 and 1871, and remain the only walled city in North America north of Mexico. The walls encircle the Upper Town, passing through four historic gates — Porte Saint-Louis, Porte Saint-Jean, Porte Kent, and Porte Prescott — and can be walked on their full length in about an hour.
Parks Canada maintains the walls and offers guided tours from the interpretation centre on the Rue d'Auteuil. Walking the top of the walls gives a different perspective on the Old City: looking inward over the historic rooftops, and outward over the modern city that developed outside. The views from the wall sections near the Citadelle toward the Plains of Abraham and the St. Lawrence are among the best in the city.
story: "The walls were never seriously tested militarily. The most dramatic moment came not from an invading army but from a fire in 1845 — one of two catastrophic fires that destroyed much of the Lower Town. The walls helped contain the fire's spread, likely saving the Upper Town."