Believing the way north to Rollbahn B was blocked, and knowing that 12th SS Panzer was well behind him, unable to dislodge the Americans from either Elsenborn Ridge or Domaine Butgenbach, Peiper and the 1st SS Panzer Division were forced to choose the more difficult Rollbahn D to the south. The road was narrow, in many places single-track, at times unpaved. When Peiper reviewed his newly assigned alternative route on a map, he exclaimed that the road was "suitable not for tanks but for bicycles!" The route forced vehicles to tail each other, creating a column of infantry and armor up to long, and prevented them from concentrating their force.