The skyscraper towers upside down from the top to the foundation in Spain

Unlike any other building, the Torres de Colón twin towers (Columbus Twin Towers) were built upside down but still ensuring safety and sustained after decades.

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Torres de Colón Twin Towers (Columbus Twin Towers) is also known as El Enchufe (Sockets) due to its shape like a giant electrical outlet. Located on Plaza de Colón in Madrid, Spain, Torres de Colón has become a symbol of the city since it was built in 1976.

Twin towers through each stage of construction.(Photo: Amusing Planet.)

At first, two central pillars were poured on concrete. The top floor was built first and hung with steel cable. After that, the engineers continued to build the remaining floors one after another from top to bottom. The entire twin towers had only the last three floors, including the basement, built from the bottom up. The structure on the roof is like the last added socket. Glass cladding is chestnut brown and green.

This special top-down construction method allows the floors of the building to be built from above and hoisted up without moving workers, construction materials and equipment from one floor to another. This technique significantly saves construction costs and time.

Although unique and impressive, many people believe that Torres de Colón is the worst building in Madrid with the roof of the green art deco style and the glass of copper tiles.

Before Torres de Colón, many other buildings were built according to this special method such as the Irish Central Bank in Dublin and the Johannesburg Standard Bank Center, three buildings in Poland and a building in Bulgaria.

Graphic simulation of the process of building towers.(Video: YouTube.)