Final answer:
The Peace River is the waterway that flows from northern British Columbia into northern Alberta before reaching the Slave River. This river is an integral part of the Mackenzie River system that drains into the Arctic Ocean.
Step-by-step explanation:
The Peace River is the river that flows from northern British Columbia into northern Alberta and flows into the Slave River. Originating from the Rocky Mountains, the Peace River traverses Alberta, playing a significant role in the hydrological network of the region. The Slave River, in turn, is part of the wider Mackenzie River system, which ultimately drains into the Arctic Ocean.
Rivers serve as crucial arteries of trade and sustenance for civilizations, akin to the role that the Limpopo River served in southern Africa's historical trade routes, or the significance of the Nile River in Sudan and Egypt. Rivers not only support economic activities but also influence migration patterns, agricultural development, and the rise and decline of empires throughout history.