Please answer the following question: What are the names of the two major river systems fur traders arrived on to get to Manitoba?  Answer the above question based on the context below:  Manitoba ( (listen)) is a province at the longitudinal centre of Canada. It is often considered one of the three prairie provinces (with Alberta and Saskatchewan) and is Canada's fifth-most populous province with its estimated 1.3 million people. Manitoba covers 649,950 square kilometres (250,900 sq mi) with a widely varied landscape, stretching from the northern oceanic coastline to the southern border with the United States. The province is bordered by the provinces of Ontario to the east and Saskatchewan to the west, the territories of Nunavut to the north, and Northwest Territories to the northwest, and the U.S. states of North Dakota and Minnesota to the south. Aboriginal peoples have inhabited what is now Manitoba for thousands of years. In the late 17th century, fur traders arrived on two major river systems, what is now called the Nelson in northern Manitoba and in the southeast along the Winnipeg River system. A Royal Charter in 1670 granted all the lands draining into Hudson's Bay to the British company and they administered trade in what was then called Rupert's Land. During the next 200 years, communities continued to grow and evolve, with a significant settlement of Michif in what is now Winnipeg. The assertion of Métis identity and self-rule culminated in negotiations for the creation of the province of Manitoba. There are many factors that led to an armed uprising of the Métis people against the Government of Canada, a conflict known as the Red River Rebellion. The resolution of the assertion of the right to representation led to the Parliament of Canada passing the Manitoba Act in 1870 that created the province. Manitoba's capital and largest city, Winnipeg, is the eighth-largest census metropolitan area in Canada. Other census agglomerations in the province are Brandon, Steinbach, Portage la Prairie, and Thompson.
A:
Winnipeg River