“We are speaking as Berliners,” the two Brazilians tell me proudly, as they lounge in a shared workspace in the edgy Neukölln district. They’re speaking English because their German isn’t good enough yet. But that hardly matters, for Berlin is the new New York: no matter where you’re from, once you show up and don appropriately grungy clothes, you belong to the city and it to you – especially if you’re young and creative with your facial hair, as these two are. I’m meeting them to talk about a little project they’ve started, not for money but out of conviction, which is why they prefer to remain incognito. Technically it classifies as vandalism, but it’s vandalism in the interests of the beauty and design of Germany’s most famous monument.

The Brandenburg Gate is the symbol of Berlin. Built by a Prussian king during the French revolution, it has Doric columns that support a quadriga on top, in which the goddess Nike brings triumph back to the city from the west on her four-horsed chariot. In effect she is Germany’s Forrest Gump, eerily present whenever anything interesting happens in German history.

Napoleon, after he humiliated Prussia on the battlefield in 1806, abducted her to Paris; she returned only after his defeat in 1814. When the Nazis seized power on January 30th 1933, they marched beneath her through the gate in a torch-lit procession. When the Allies divided Berlin in 1945, she suddenly found herself on top of the Iron Curtain, riding into the Soviet sector with her bum facing the British one. From 1961 that curtain became the Berlin Wall, which passed right in front of the gate (on its western side). “Mr Gorbachev, open this gate! Mr Gorbachev, tear down this wall!”, Ronald Reagan demanded in 1987, standing right there. Two years later, the gate really was opened. So today, this is where you go when you want to have all that as your psychic backdrop, or when you’re just looking for a centre in a dispersed country. When Germany’s footballers win, the players naturally come, like Nike, to the gate to celebrate.

All of that is great and works in part because the neoclassical gate itself is beautiful, the two Brazilians agree. The problem is the kitsch it has spawned. Today its image is found, like that of the Eiffel Tower or the Statue of Liberty, on every surface imaginable, from cups to puzzles, walls to flags. In varying degrees of abstraction the gate serves as a logo for almost anything connected to Berlin. And that brings us to BVG , the city’s public-transport company, which runs the underground, buses and trams.

Naturally BVG also uses the gate as its logo. It has in fact plastered the logo all over the windows of its trains. But the gate in these pictures looks as though it has been doodled by a two-year-old child. Its lines violate all laws of perspective, the quadriga is a hairball of squiggles, and the whole thing lacks proportion. As design it is embarrassing.

Such sloppiness is typical of Berlin. The city is surprisingly ugly and inefficient. Some eyesores are scars of the past, places where architects have not yet built over the detritus of war and division. Others are products of an un-Germanic and yet quintessentially Berlinish carelessness: the idea that things going pear-shaped is somehow cool. For instance, I have, like countless Berliners, tried all year to book an appointment online to get some paperwork done by the city administration. Hopeless. The city’s new airport was supposed to open in June 2012 but keeps being delayed because of construction snafus. (The latest plan is to open in December 2017, but I don’t know anybody here who believes that.) Deep down Berliners savour all this, because it is fodder for their “Berlin snout”, a wickedly biting form of local humour.

What makes this dysfunction charming is how Berliners cope with it. The city arguably has the world’s most cutting-edge graffiti scene. The two Brazilians are in that tradition. Inspired by the freak gate on the BVG logo, they designed transparent stickers which you can layer over the logo to improve it.

In late June they printed a first batch of 10,000 stickers and discreetly made them available for public use. All were snapped up within a couple of weeks. A second batch is on the way this month. Stealthily and anonymously, civically responsible vandals are beautifying their underground system.

I contacted BVG to find out what they think about all this. Shocked? Not quite. “Delighted,” said a spokesman in an email to me. “If somebody takes such care for the perspective of the gate on our window stickers, he must really have our underground system close to his heart.” The next day, BVG issued a press release. A new and better design is on the way, (although the stickers will be glued on only gradually, as trains are taken out of service for maintenance). “We had to get something straight,” the release reads, even though “we are tolerant of everything crooked.” Quite so.

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