Its formal name is Torres de Colon or the Columbus Towers.
Some say it is the ugliest building in Madrid.
Nevertheless, Torres de Colon has been an icon of Madrids skyline since it went up in 1976.
Construction stages of Torres de Colon.
The first thing that rose was the two central pillars on concrete footings.
Then the top-most floor was raised and hung with steel cables.
The rest of the floors followed from top to bottom.
Only the bottom three floors including the basements were built from bottom up.
The glass facades are covered with maroon and green and the plug-like structure was added later to the top.
Construction of Torres de Colon
The central towers of Torres de Colon without the floors.
Although an uncommon construction technique, Torres de Colon isnt the only building to be built this way.
There are at least three buildings in Poland built top to bottom.
The Trzonolinowiec, built in 1961-1967, is sometimes referred to as “hanging man”.
It stands in Wrocaw.
The other two stands in city of Gdansk, and Katowice.
The Bulgarian city of Sofia also has such a building, built in the 1970s.
A variation of this technique was developed in The Netherlands.
Its called the Jackblock.
It is then jacked up an amount equal to its exact height and another is built underneath it.
These three floors are jacked up and so it goes until the building has reached its exact height.
It is then anchored to the foundations.
Pre-cast floors raised to build a residential block in Magnitogorsk, Russia.
The house as it appears today.
Sources:Secret Madrid/Wikipedia/www.zdanija.ru/Construction Updates/engineering-ru.livejournal.com
