The Borovnica viaduct, sadly no longer standing, was built in 1856 on the Südbahn or Southern Railway, the first railway line linking Vienna to Trieste. It was one of the most imposing bridges ever built in Slovenia and in its day one of the most imposing bridge structures the world had ever seen. The only bridge larger than the Borovnica viaduct was the Göltzschtal viaduct at near Plauen in Germany (built in 1854 and still standing today).
The spans of the Borovnica viaduct were not particularly large but because of its size it was one of the most interesting bridge structures from the mid-19th century. The 561-metre-long, 38-metre-high viaduct was designed by the Southern Railway’s famous engineer Karl Ghega (a Venetian by birth). Owing to the marshy ground on which it was to be built, the viaduct was placed on 4,000 wooden piles. The piers were built of limestone blocks while the 47 arches (22 in the lower tier and 25 in the upper tier) were built of brick – 5 million bricks, to be exact.
As a result of a drop in the level of ground water during drainage of the site on which the viaduct stood, the wooden piles slowly began to rot and the viaduct began to decay inexorably. Still an important railway viaduct, it was finally destroyed by Allied air attacks during the Second World War. Today only one surviving pier shows where the Borovnica viaduct once stood.