When you visit Washington D.C., you really don’t see much of the Potomac River. As you enter the city, you cross over it, but don’t pay much attention because you’re fighting traffic. Later you catch a glimpse from a few memorials, such as the Washington and Jefferson Memorials in this photo. I understand there are some tours on the river. I bet that would be a great vantage point for memorial photos that you can’t get from any other vantage point.