Because dense forests made overland travel in North America very difficult, Indians and Europeans used waterways whenever possible. Lake Champlain, the longest of these waterways, provided a link between two major rivers. Although the French dominated the northern end of the lake, the southern sector and Lake George remained in contention. In 1755, the governor of Canada ordered the construction of Fort Carillon (Ticonderoga) at the place where travelers had to move overland between Lake Champlain and Lake George. Sir William Johnson responded by erecting Fort William Henry at the southern tip of Lake George.