National Redoubt (Switzerland)

The Swiss National Redoubt (German: Schweizer Reduit; French: Réduit suisse; Italian: Ridotto nazionale; Romansh: Reduit nazional) was a defensive plan developed by the Swiss government beginning in the 1880s to respond to foreign invasion. In the opening years of the Second World War the plan was expanded and refined to deal with a potential German invasion. The German plan, Operation Tannenbaum, was real, but was never carried out. The National Redoubt primarily refers to the fortifications begun in the 1880s that secured the mountainous central part of Switzerland, providing a defended refuge for a retreating Swiss army.

The National Redoubt encompassed a widely distributed set of fortifications on a general east-west line through the Alps, centering on three major fortress complexes, Fortresses St. Maurice, St. Gotthard and Sargans. These fortresses primarily defended the alpine crossings between Germany and Italy and excluded the industrialized and populated heart of Switzerland. The Swiss heartlands were defended by the Border Line, an advanced line of defenses near the borders, and the Army Position somewhat farther back. While not intended as an impassable barrier, these lines contained some significant fortifications. The National Redoubt, however, was planned as a nearly impregnable complex of fortifications that would deny an aggressor passage over or through the Alps by controlling the major passes and the railway tunnels running north-to-south through the region. This strategy was intended to deter an invasion altogether by denying Switzerland's crucial transportation infrastructure to an aggressor.

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