In "The Council of Elrond" Boromir states that he has journeyed one hundred and ten days to reach Rivendell from Minas Tirith. Why did it take him so long? Gimli states that Mordor to the mountains above Moria is 300 leagues which is 900 miles (when they are contemplating the Redhorn pass). Minas Tirith is a bit nearer, but they've travelled south from Rivendell so I estimate his journey at 1000-1100 miles. So at best he's averaged 10 miles/day even though he's a strong determined man on horseback. I just can't reconcile that journey time with the known dimensions of Middle Earth.