Fort Washington, United States offers 1 beach perfect for sunbathing, surfing, swimming, and more. Fort Washington, Maryland, United States, is known for Fort Washington Park, which features a historic fort with scenic views of the Potomac River. The best time to travel to Fort Washington, United States, is in late spring (May), when the average air temperature is around 70°F (21°C) and the nearby Potomac River water temperature is approximately 65°F (18°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!