Stayed here for Marine Corp Marathon 2011, it was great.
I got lost finding it. so if you are catching the Metro to Foggy Bottom, turn right and back on yourself when you come out of the station. Walk through a pedestrian area and keep going. Cross and odd road junction with a 7/11 on the right - but keep going. At the next junction, turn right and The River Inn is on the left.
Breakfast is not included, it is expensive and not worth the wait.
But the staff are great, the location is perfect and the rooms clean, tidy and the bed - AWESOME!!