Montreal itself, at the head of the colony, at the beginning of its hinterland, commanded the junction of the Ottawa and the St. Lawrence. At Cataraqui, where the St. Lawrence leaves Lake Ontario, Fort Frontenac was built. A little above the outlet of the Niagara river into Lake Ontario and below the falls, another French fort was reared, Fort Niagara; while on the channel between Lakes Erie and Huron was the fort of Detroit. The Iroquois, as we have seen, knew as well as the French the value of these positions: they feared and resented the building of the forts, as limiting the range of their power, and taking from them the control of the fur trade. On the upper lakes there were at least two posts of prime importance: one was the Sault St. Marie at the junction of Lake Huron and Lake Superior, the other was Michillimackinac at the junction of Lake Huron and Lake Michigan. It must not be supposed that the points mentioned were occupied in chronological order, as they have been enumerated above; or that there was any regular series of occupants, that the explorer came first, followed by the missionary, the trader, and so forth: but the net result was that French enterprise and French statesmanship took and kept the gateways on the highroad of Upper Canada. [Sidenote: _Lake Michigan._] [Sidenote: _Michillimackinac._] [Sidenote: _Green Bay._] [Sidenote: _The route to the Mississippi from Green Bay,_] Lake Michigan was known to the French as the 'Lac des Illinois.' The narrows where it joins Lake Huron were the straits of Michillimackinac, now Mackinac or Mackinaw; and on their northern side stood the trading station of the {150} same name, and the mission of St. Ignace. Within the straits on the western side, is a large indentation, forming a sheet of water which runs south-west, nearly parallel to the main lake. This was at first called, after certain Indians who lived on its shores, the Baie des Puans; but it was subsequently named the Grande Baie, and this title was corrupted into Green Bay, its present name. The Fox river flows into the head of Green Bay, and, if the upward course of this river is followed through Lake Winnebago and beyond, a point is reached at which the waters of the Wisconsin river are not more than a mile and a half distant. The Wisconsin is a tributary of the Mississippi. [Sidenote: _and from the end of Lake Michigan._] A slightly longer portage was needed to reach the Mississippi basin from the end of Lake Michigan. Still it was a matter of very few miles to leave the lake, where the city of Chicago now stands, and to strike one or other of the branches of the Illinois river, the nearest being the stream known as Des Plaines. Canoes launched on that stream were carried down into the Illinois, and so to the Mississippi at a point far south of its confluence with the Wisconsin. [Sidenote: _The Ohio route._]