Montréal sits on an island where the water wraps around the city and the land rolls into gentle hills. Down in the old quarters, the streets tighten and the stone grows heavy. The Montreal Flow is a 2.4 km loop through this dense core, sliding past the walls of Château Ramezay and the air of Maison Papineau. It takes 10 corners that require a steady hand, and the whole thing plays free in the browser with no account or install. From a rooftop perch, the loop looks like a ribbon tied around the history of the town.