In a city that once bent to the state's will, individual expression is now a freedom to be prized for some of the world’s most talented artists.

The streets of Berlin – and the art that adorns them – have long had a story to tell. From murals that depict the trials of German reunification to paste-ups that comment on current events, the city's graffiti is a record of its history and its people. And many of Berlin’s finest international artists use streets, buildings and public spaces – not canvases – to host their masterpieces. But if you don't know where to look – or don't know what it is you're looking at – it's easy to miss the narratives being told.

When the city was divided between East and West Germany, early street artists like French artist Thierry Noir used the western side of the wall as a place to share political messages and commentary on Berlin and the world at large. Noir is known as one of the first and most prolific of the wall’s artists; he began painting graffiti on the wall in 1984 and now his work is now featured prominently in the East Side Gallery, a 1.3km section of the wall that displays more than 100 murals by artists from 21 countries. The paintings were done in 1990, a year after the city was reunited.

Today, however, the gallery is under threat of demolition to make way for luxury housing and a 14-storey hotel. A 6m stretch was temporarily removed during construction, and the hotel’s developer has asked for 20m of the wall to be removed permanently to accommodate a driveway. For now, however, the wall remains one of Berlin’s most evocative examples of artistic expression.

After the fall of the wall, artists from West Germany moved to neighbourhoods like Friedrichshain in the former East Berlin, lured by cheaper rents and an abundance of untouched canvases. They covered buildings in political statements and popularised tagging – the art of signing one’s name and expressing one’s identity – after years of being forced to blend in as part of the Communist machine.

Today, street art in Berlin ranges from tiny tags to massive murals, and two of the city’s most famous pieces sit side by side on four-storey buildings along the river in Kreuzberg.

Both pieces were done by the Italian-born artist Blu. The first (pictured here), painted in 2007, has been called both Wall and Brothers. It shows two masked figures; one is upside down and forms an E with his fingers, the other is right side up and forming a W with his. The two men, making the signs for East and West, are trying to rip one another’s masks off. It’s a powerful symbol of the challenges faced by the people of the formerly divided city as they reunited after living side-by-side as strangers for more than 30 years.

The other piece (also pictured), painted a year later, shows a headless man in a crisp shirt, straightening his tie. On his wrists, gold watches form the chains that shackle him. Painted in 2008, Blu’s commentary on a professional’s enslavement to time, money and materialism speaks to the conditions in Berlin today. Residents worry about rapid gentrification, as housing costs rose more than 30% from 2007 to 2013. Berlin is also fast becoming a major hub for innovation: by the beginning of 2014, there were more than 2,500 start-ups in the city, including the popular music-sharing platform, SoundCloud. 

Another mural by Blu, painted in 2007, encourages similar reflection. Located on the western side of the Oberbaumbrücke Bridge in Kreuzberg (recognisable from the 1998 movie Run, Lola, Run) a pink monster threatens to eat a tiny white figure (pictured here). The pink monster, with its white lifeless eyes, is actually made up of hundreds of tiny pink humans, perhaps illustrating that conformity creates an individuality-killing monster. In a city where residents were once forced to bend to the will of the majority, it’s a sobering reminder that individuality, for so long stifled, is now a freedom to be prized. 

Though street art remains illegal in Berlin, many building owners have chosen not to fight the inevitable. Rather than wait for their buildings to be tagged, owners sometimes pay artists 300 euros or more to create murals for their properties. Tagging over another artist’s work is considered a great insult, so commissioning a piece is a smart if counterintuitive way for owners to be sure that the art on their building will at least be art that they like.

El Bocho is one of the most well-known street artists currently working in Berlin. Originally from Frankfurt, he has several highly recognisable motifs around the city. One is Little Lucy, a cat-hating little girl inspired by a 1970s television series of the same name. Little Lucy can be seen all over Berlin, devising ever more inventive ways to kill her cat, including ripping him in two, carving him like a kebab and serving him in a sandwich, drowning him, boiling him in a pot and hanging him with a rope.

Here, Little Lucy has wrapped her cat up in a box, perhaps to give him away.

Most of the Little Lucy art is done by paste-up, meaning the artist creates the piece on paper and then affixes it to a wall with paste. Some artists prefer to work this way as it allows them to create intricate works in a safe place and then quickly put it on the streets. The less time an artist has to spend putting his art in the public space, the less chance he’ll be caught by police. Additionally, paste-ups carry a lesser charge than other street art; it is considered littering and is punishable by a lesser fine than graffiti, which can range from 100 euros to two years of jail time.

The work of London-based, Australian-born artist James Cochran, also known as Jimmy C, looks almost impressionistic. His paintings, on canvas and on the street, are made of thousands of tiny dripping dots that – when viewed from farther away – create beautiful human portraits. His work can be seen around the city, but one of the most intriguing is his self-portrait, the Artist’s Tears (pictured). Originally painted on canvas in 2002, it was recreated as street art on Revaler Strasse in 2012 in the Friedrichshain neighbourhood.

Revaler Strasse is a popular place for street art. The street and surrounding area make up a former industrial site that built in 1867 as home to the Royal Prussian Railway Workshop (the Reichsbahnausbesserungswerk, where German railway carriages went for repair). The neighbourhood was later used by the German Democratic Republic until 1989 as a site for industrial factories. When it was officially decommissioned in 1994, artists moved in and began using the empty buildings and crumbling blank walls as their canvas. The area is now home to the Skalitzers Contemporary Art gallery, which focuses its exhibitions on street art.  

Down the street from Skalitzers on Revaler Strasse, Spanish artist Rallito-X has left his mark with a mural of a grotesque multi-eyed monster with several legs (and a few other extra appendages), painted in 2012 (pictured). The message above the monster, “Greetings from Spain”, reveals the monster to possibly represent the EU financial crisis that began in 2009 when several European countries, including Ireland, Spain, Italy and Greece, hit hard by the global financial slump turned to the EU for bailouts.  

Mein Lieber Prost’s work (pictured) is more enigmatic. It hides in doorways or high on walls; the faces and characters quietly point and laugh, possibly mocking the passerby who might not even notice. No one knows the Berlin-based artist’s identity, but his simple work, which began popping up as early as 2009, is now so ubiquitous and instantly recognisable that he often doesn’t even sign his name.  

The work of another anonymous artist, Alias, is more complex, both in style and in meaning. Done with stencils, most of his pieces depict solo figures in black, white and grey, with deep reds and blues occasionally used for emphasis. A faceless teenager in a hooded sweatshirt sits cross-legged, another boy rests on a skateboard with his back turned to the viewer. In one of Alias’ recurring images, a small boy sits, looking dejected, on a bomb with a lit fuse. While Alias, who started in 2004, works mostly on the street, he also creates images on found objects like metal scraps and cardboard, some of which are sold at the Open Walls Gallery, a site that commands as much as 600 euros for a piece of graffiti.

Over the last 30 years, street art has become a core part of Berlin, as synonymous with the city as the wall that once divided it. The images that decorate the city tell its stories – sometimes tragic, sometimes funny, sometimes controversial and, sometimes, beautiful.  

CORRECTION: A previous version of this article incorrectly stated the location of Berlin's Kreuzberg neighbourhood. This has been fixed.