Long before any Indians tribes or fur traders claimed these lands as their own, large glaciers cut valleys through the surface of the earth. Many of these glaciers reaching a mile high pushed rock and debris from place to place as they advanced. As these glaciers of the last ice age started to recede, they left large lakes in their wake. Lake Maumee, one of the largest, spanded from present day Fort Wayne northeast to merge with Lake Erie. Eventually, Lake Maumee began emptying into Lake Erie. The rivers that were left would shape the area of northeast Indiana forever.
The glaciers had caused the St. Joseph and St. Mary rivers to sharply change course and flow together to form the Maumee river. What was left by the glaciers was to become one of the most traveled areas of the northwest wilderness. There was only a very short "land barrier" that separated the fur traders from Quebec from the fur merchants of New Orleans. The abundance of beaver fur in the three rivers area was the most of any in the territory.
The Portage, a french word meaning "carrying place" was the most important trading route in the northwest territory. The Miami considered it a sacred "gate" that was to be protected at all costs. From the earliest times, the Miami became very wealthy extracting a toll on those who used the portage. The French were the first europeans to use the route. As the fur trade grew, so did the French presence in the region. As early as the 1690's the French were creating a fur trading empire from Quebec to New Orleans.
A French explorer by the name of Robert Sieur de La Salle believed that a stronghold near the portage was essential to connecting French New Orleans with French Quebec and keeping the wealth of fur trading solely in French hands. The French and their Indian allies opened a fur trading post north of the portage on the St. Mary's river in what is today Guldin Park. It was only a few years later that the French considered a permanent military presence important. Captain Dubuisson, the commander at Detroit, built the first fort in the three rivers area called Fort Miamis.
