Ajax, Canada offers 3 beaches perfect for sunbathing, surfing, swimming, and more. Ajax, Ontario, Canada, is known for the scenic Waterfront Trail along Lake Ontario and the historic Pickering Village. The best time to travel to Ajax, Canada, is during the summer months of June to August, when the average air temperature is around 70°F (21°C) and the water temperature in Lake Ontario 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!