Hello how may I help you? i have a question about the city of montreal What would you like to know? can you tell me the name of the river the city is on? Montreal is on the St. Lawrence River. How big is the St. Lawrence River The St. Lawrence River is 743.8 miles long. Can you tell me one more interesting fact about Montreal? Montreal is one of the five largest French speaking cities in the world. Thanks, I didn't know that! No problem! Is there anything else you'd like to know? Nope, that's it.