Final answer:
The St. Lawrence River is the famous river in Quebec, located in the valley between the Appalachian Mountains and the Canadian Shield, playing a key role in the province's development and culture.
Step-by-step explanation:
The famous river in Quebec is the St. Lawrence River. It is located at the heart of Quebec, creating a valley between the Appalachian Mountains and the Canadian Shield. The river is integral to Quebec's geography and history, as it provided a critical transportation route and was a site where early French settlers, led by explorers such as Jacques Cartier, established settlements. Quebec City itself is built at the original head of navigation on the St. Lawrence River, and the name 'Quebec' originates from an Algonquin word meaning "where the river narrows."
Today, the St. Lawrence River is still central to Quebec, flowing through major metropolitan areas like Montreal, the largest French-speaking city in the Western hemisphere. The river's presence has shaped the social, economic, and cultural landscape of the province, with industries and communities historically flourishing along its banks.