Why couldn't the Wildlings have crossed the River west of the Shadow Tower (named the Gorge)?

[Guest]

(This is my first time as OP, so forgive me if this is in the wrong place. I believe this pertains to the world of ice and fire)

While looking at a map of Westeros today, I noticed that the Wall stops at the Gorge River. Could Mance Rayder have crossed over the River, given enough time? The Shadow Tower probably patrols the area, but with very few men. If I recall correctly, someone on the wall said there are only three rangers for every mile of the Wall. This was at the beginning of the series, where the Night's Watch had less than a thousand. After the Great Ranging, which had costed the Watch a third of its men (300 men) and had only 30 men return, there are now approximately 600 men of the Night's watch. This brings the total number of men per mile on the Wall to 2 men per mile. Now, AWOIAF.com (specifically, http://awoiaf.wester.../index.php/Wall) says that "and to the west the mountains and deep riverGorge, make the terrain impassable for all but small groups of raiders" but if enough groups of small raiders get over the mountains and the river, that's still enough to do a substantial amount of damage to the Night's Watch, especially since the Night's Watch is undefended from the South. Again, forgive me if this has been discussed before, is in the wrong subforum, or is just stupid.

[Toccs]

Mance sent the Weeper and his band of raiders to the Gorge during the attack on the Wall. Bowen Marsh was injured in the resulting Battle on the Bridge of Skulls.

[Guest]

Ah. Thank you.