How did fjords form an important part of British Columbia’s coastline?

Fjords are a defining feature of British Columbia’s coastline, formed through the geological process of glaciation during the Pleistocene Epoch.1

During this period, massive ice sheets covered the Coast Mountains, and their glaciers moved through and deepened existing stream valleys. Because these glaciers were incredibly heavy and active, they eroded the valley floors far below sea level. As the climate warmed and the glaciers melted, the sea flooded these deep, U-shaped valleys, creating the narrow, winding inlets known as fjords.123

These fjords are integral to the province's geography, as they twist inland around the bases of towering mountains, creating a highly indented coastline. By providing a protected waterway along the coast, they facilitate navigation and contribute to the region's unique physical character. In many cases, the rivers that originally carved these valleys have reestablished themselves, depositing sediment at the fjord heads to form deltas, which often serve as the primary locations for human settlement in these rugged areas.312