The server centre in Luleå is Facebook's first to open outside of the U.S., and will handle information from the social networking site's 350 million users in Europe.
The server facilities, which will benefit from Luleå's arctic climate, are about the size of 11 or 12 hockey rinks lined up one after another.
When the Facebook founder Mark Zuckerberg first visited the town and uploaded a photo of it he got half a million 'likes' in minutes and helped to crash some of the city's internet servers as people around the world rushed to find out where Luleå was.
At Wednesday's press conference Marita Ljung from the Swedish government's department of industry, said she was proud of what Sweden can offer and that Facebook had chosen Luleå.
Facebook received over SEK 100 million in Swedish state financial support to build the data centre.