Saint Charles sur Richelieu, Canada offers 1 beach perfect for sunbathing, surfing, swimming, and more. Saint Charles sur Richelieu is known for its picturesque riverside views and historic architecture. The best time to travel to Saint Charles sur Richelieu, Canada, is during the summer months of June to August, when the average air temperature is around 70°F (21°C) and water temperature is approximately 68°F (20°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!