Norway's coastline is so deeply cut by fjords that its full length is extraordinary.

The longer version

Fjords are valleys carved by glaciers and then flooded by the sea. Moving ice deepened and straightened existing river valleys, cutting them far below current sea level. When the ice retreated, seawater filled the troughs, producing long, narrow inlets with steep walls. Many are deeper than the shallows at their mouths.

Measuring such a coast depends on scale. A detailed outline that follows every inlet totals many times the length of a smooth, generalised line. This property means longer coastlines appear the more closely you look. The sheltered water also made coastal settlement and fishing possible for centuries, since boats could lie safe in almost any weather.

Where this entry sits

These facts wander across maps, borders, deserts, rivers, mountains, and the extreme corners of the natural world. Each one is short and self-contained, offering a small surprise about places you may never visit rather than anything you actually need. The full list sits on the Geography page, where every entry is listed in order.