- Hannibal’s army was directed by guides.
- He had the animals walk carefully through narrow places.
- He had his men clear vegetation.
- He had his men build roads.
- He had his men follow the contours in the mountains.
- He hit detours at cliffs and was misled by guides from time to time.
- He had his men clear away snow and ice.
- He had his men cut through rock to create paths by quickly heating frozen rock, using sour wine as a corrosive, and then using picks.
- He had his men create a zig-zag track to minimize the slope of the road during the group’s descent.
- The elephants took longer to move over the top of the mountains than the men and horses because they had to widen the path.
- The animals had to eat local vegetation along the way, so the animals almost starved while they were stuck at the peak.
- The Italian side of the Alps has ample vegetation, so once Hannibal got the army over the top of the mountain, the party was able to feed the animals and rest.
*Notes based on information from http://www.livius.org/ha-hd/hannibal/alps_text.html