Long day on the road

We left Minneapolis about 6:30am.  We had some fog, roads were a bit slick, nothing too bad.  Then all cleared and we made good time until we got into a major 2 hour traffic stall.  A truck had turned over spilling their load. We decided to stop sooner than we had planned at Clarksville,  TN.  It was 10:30 pm and we were exhausted.