I guess this is the rental shack for the paddle boats. I have seen them on the water before but have never bothered to rent one. When I took the image the dock was closed so I could not venture out on it.
While the shack appears to be the focal point of the image and I guess it is, I really like the National Aquarium lit up in the background. It just draws the eye from the shack to that.
This is one of those images that I wish I had a tripod with me but because I didn’t plan on anything I just had my Sony RX100. I think it could be much sharper if I shot it at a lower ISO and on a tripod. A stable shooting platform I am not.