The other major alternative to foraging for large armies would be to resupply by boat (which could travel much faster than a marching army). The benefit of this was that the army could now spend all that extra foraging time marching twice as much, however, this wasn't always possible unless the army followed a river or a coast. These two options played heavily in the Third Crusade: Richard the Lionheart was successful as long as he stayed on the coast, resupplied by his ships. Saladin knew they would eventually have to march inland to the ultimate goal of Jerusalem, so he adopted a scorched earth strategy to prevent the invading army's ability to forage by poisoning wells and clearing the land of animals. When they finally did march to Jerusalem, they had to rely on supply caravans from the port of Jaffa, which were vulnerable to attack by Saladin's light cavalry.