Pylons of Messina

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The Pylons of Messina are the pylons of the former above-ground 220 kV high-voltage line crossing the Strait of Messina between Italy and Sicily, part of a longer power line from Sorgente to Rizziconi.

The pylons are two 200 metre high freestanding steel towers, one on Sicily and the other on the Italian mainland. In a difference from usual practice, the corners of the pylons are arranged diagonally along the direction of the course of the line. The pylons of Messina were the model of the pylons of Elbe Crossing 1 in Germany and were, until the completion of Elbe Crossing 2, the highest pylons of the world.

After their completion, the period of the oscillation of the structures and their maximum deflections were determined in a very unusual manner: engineers mounted three rockets with a thrust of 9800 kilonewtons on the tops of the pylons and ignited them ^[1].

Because the overhead power line over the Strait of Messina has a very large span width (more then 3 kilometres), and because of the maritime traffic in the strait below, the conductors must have a great minimum height above ground, and had to be constructed to have great tensile strength. This required the use of steel cables as conductors even though steel has the disadvantage of less electrical conductivity than normal overhead power lines. The danger of oscillations caused by wind did not allow the usage of bundled conductors. Thus, the original overhead line across the strait did not meet modern operational standards and the entire power line was replaced at the end of the 1990s by a submarine cable.

The now-unused pylons remain, with protected status as historical monuments.