^^
https://campgrounds.rvlife.com/regions/quebec/st-mathieu-de-beloeil/camping-alouette-3989 when we stayed we took the ferry across the river to visit Montreal/Old Montreal as they have a large commuter lot for parking. If I remember correctly ferry leaves every hour. Campground has directions, worked out well for us.
yeah traffic is heavy around Montreal, especially during commute hrs. As mentioned campground has easy in/out level FHU sites. Park was well maintained.
Everything is urban so you will hear city noise, that said I remember the back part of the park somewhat quieter but don't expect to hear crickets.
2 days visit worked well for us
Mike