Have Google Maps open to Montreal. Discuss some of the geographic features that make Montreal a unique city. Examples that students might come up with: it's an island; the oldest parts of the city are located close to the water and in the centre of the island; the mountain is still the dominate geographic features and physically divides the city.
Once the students have discussed, you can use "Street View" to show students some of the landmarks of the city. Landmarks can include: the mountain, the Old Port, McGill University, Mary Queen of the World Cathedral, Bonsecour Market, etc.