The one with the piece of metal stuck on one arm of the cross.
That cross was found standing upright in the rubble, had come from WTC 1 (North tower) and fell through the roof of building 6. There were actually several crosses in the same place, and the worker who found them spray painted "God's House" on the wall nearby. The one big cross with the metal piece was moved to a more visible location on Oct 3 (2001). This photo shows where it was found originally.
and this shows where it was moved.