An enduring reminder of the communist era, the vast, concrete "Plattenbau" tower blocks that surround cities in eastern Germany are usually considered eyesores rather than works of art.

Yet, a new urban culture project in the city of Halle, 170 kilometres (around 100 miles) southwest of Berlin, hopes to promote social cohesion by transforming architectural sins into monumental masterpieces.

By brightening up the grey blocks made of prefabricated concrete slabs and often associated with poverty and tensions, artists aim to get people who don't normally interact talking.

A mural by the urban art collective "Freiraumgalerie." AFP

Adorning the side of one block, a three-dimensional mural in vivid colour depicts an astronaut descending from a satellite-like spaceship via a wooden ladder held by two men far below him.

In the background is a clear blue sky, giving the illusion that the walls have disappeared.

What could be a Pink Floyd album cover is in fact a work called "Balance Act" by the Freiraumgalerie artist and urbanist collective.

"The artists chose this blue because they wanted to turn the hard and severe architecture of the Plattenbaus into something softer," says collective member Philipp Kienast.

A mural by Sabek of the urban art collective. AFP

The seven-million-euro ($7.7-million) project, which once finished will cover 8,000 square metres (86,000 square feet) of wall space on four buildings, was commissioned by HWG, the housing association responsible for the blocks.

Everything is always changing

When HWG began a full-scale refurbishment of the buildings in 2018, the idea was to create "something original with which the residents could identify", says association managing director Juergen Marx.

A mural by the urban art collective. AFP

They enlisted Freiraumgalerie, a collective known in Halle for reviving ageing buildings with vibrant graffiti, who actively involved locals in the "Balance Act" project.

"We invited residents to pose in different ways, photographed them, and then painted people in the same positions," says Kienast.

Even if they did not paint exact likenesses, residents would be able to recognise themselves on the building, he added.

The urban art collective decorates a residential building owned by the HWG housing company in Halle.

For resident Elfriede Schulz, a 79-year-old former teacher who has lived in the complex for over four decades, the project is a resounding success.

"People always say 'oh you live in the Plattenbau'," she says, miming an expression of disgust.

"I don't like that, so I'm happy that these creations and colours can bring something good to the building."

Social unrest, crime

Nowadays, said Marx, the residents are more likely to belong to disadvantaged sectors of society. He estimates that around 40 percent of them are foreigners.

Juergen Marx, managing director of the HWG housing company, poses next to a giant mural 

In Halle, as in other East German cities, the Plattenbau complexes which surround the picturesque old town can be a backdrop for social unrest.

One of them, Neustadt, is notorious for its high crime rate and for being one of the poorest communities in Europe's biggest economy.

Yet Marx hopes that art projects such as the one in Halle can help to strengthen community ties.

"When people know each other, everything becomes easier," he says.

Freiraumgalerie's Kienast agrees.

"In the places where we paint, people generally don't have good social contacts with each other," he said.

"When they look at our walls, even if they argue about it or don't like it, it is a good opportunity for people to approach each other and talk about the art.

"That is something they would otherwise never have done."

Agence France-Presse