German data center operator Sievers has opened a facility in a former nuclear shelter.

Located in Bremen, a city in northwest Germany, the Tier 4-certified facility spans 2,000 sqm (21,527 sq ft) and became operational on June 26 of this year.

The windowless facility was supposedly built in 1944 as a bomb shelter before being converted into a nuclear shelter during the Cold War. German construction company Carbocon then helped convert the property into a data center, which was operated at the time by colo provider ColocationIX.

It is unclear when the facility passed into the hands of Sievers.

Head of Key Account Management Stefan Schneider said that the company was “consciously focusing on stable, transparent framework conditions – and thus on IT infrastructure in Germany.”

The company has repeatedly emphasized the safety of the facility, which has two-meter-thick reinforced concrete walls.

Speaking to IT Daily, Schneider said: “At a time when digital threats and global political uncertainty are increasing at an alarming rate, it is crucial to operate IT infrastructures in a stable environment that meets the highest security standards and allows absolutely no compromises. We are proud to now be able to offer our customers this high level of protection.”

Sievers is a German IT service provider. The company operates a data center in Dusseldorf, but it is unclear whether it operates more facilities.