Converting buildings originally built for military use into data centers is a fairly common practice.

Such structures already have the sturdiness and security features required by data centers.

A Nazi-built anti-aircraft tower in Vienna may become the latest example of such reuse.

The Vienna City Council is looking into leasing one of the six large flak towers the Nazis built around the city during WWII to a company that would convert it into a data center, according to a BBC report.

The tower in question is called the Leittrum. Of the six structures, the Leitturm in Arenberg Park is best preserved and some in the city government hope revenue from the lease to a private company would help offset its rising upkeep costs.

"The data center must be kept safe from any kind of terrorism," the city's Sandro Forst told BBC.

"The flak towers are made of very stable concrete, they are well located and they are very safe because of the concrete walls."

The plan is controversial because there are those in the city who believe the historic structures should be open to the public as reminders of the city's history.

"We have got right-wing politicians, and young people are starting to vote for them," said Sabine Gretner, member of the Green Party.

"And these buildings are so strong inside that you can feel the horror of war. I want people to have this feeling so that it cannot happen again."

Between 1942 and 1945, the Nazis used the towers to shoot at enemy aircraft from and as civilian bomb shelters.