försvarslinje

Försvarslinje, or 'defense line', is a concept in military geography and strategy describing a line of positions, obstacles, and arrangements intended to slow, deter, or halt an enemy advance and to protect vital territory, population centers, or assets.

A försvarslinje can be physical, consisting of fortifications, trenches, minefields, anti-tank obstacles, fire-support positions, observation posts, and logistics networks, or it can be a planned or theoretical construct used for planning. It often relies on natural features such as rivers, ridges, or coastlines to strengthen the line.

Static defense lines are designed to be held for a period and may be reinforced by reserves and counterattack plans. In modern warfare, lines of defense are frequently integrated with maneuver, logistics, air and cyber capabilities, and may form part of a broader defense-in-depth approach rather than a single fixed boundary.

Historical examples include the Maginot Line in France, the Siegfried Line in Germany (Westwall), and the Mannerheim Line in Finland.

The term is widely used in many countries to describe border fortifications or front lines in different eras. In Swedish usage, försvarslinje can refer to both historical fortification belts and contemporary defensive strategies.