Letzi

A Letzi (plural:Letzinen, also known in German as a Talsperre in the sense of a fortification, not a dam) or Letzimauer refers to defensive barriers whose purpose is to protect the entrance into a valley. The term is Swiss and these stone barriers were particularly common in medieval Switzerland, but are also found in Austria and Germany.

Letzis usually consisted of:

Because they had a combination of elements of hill and lowland castles, letzis did not fall neatly into either category.

The walls were often several kilometres long, for example in Rothenthurm SZ, and were often combined with ditches.

Such defensive valley barriers were still being built in the 19th century, for example the Forte della Chiusa and Buco di Vela.

Researchers have not been united in all respects about whether these fortifications actually served as protective lines of defence or whether, in most cases, they were just intended as border marcations and defence against cattle thieves.

What is certain is the Letzis were used to force merchants to adhere to specified routes (Straßenzwang) and thus to enable the collection of customs duties (Wegzoll) and money to pay for the maintenance of the roads.

Castle and letzi of Castelmur

The castle ruins in the Mühlbacher Klause, which guards the western Pustertal

Letzi of Mülenen Castle

Buco di Vela

Letzimauer at Näfels

Letzimauer at Oberarth

Letzi Tower in Morgarten

Porta Claudia

The Swiss German word, Letzi, comes from the Middle High German "letze", i. e. a barrier, obstacle, defensive wall or border fortification. Even today many toponyms include the words Letzinen, Letzimauern or Letzitürme. Remains of such defensive fortifications may still be seen in many places today.

Examples of Letzi in place names:

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Wikipedia