Specialty coffee in Berlin.

Berlin drank filter coffee from a drum-roasted dark blend for most of the twentieth century, in the coffeehouses of Charlottenburg and the kitchens of the East alike. The break came in 2006, when Bonanza opened on Oderberger Straße in Prenzlauer Berg and roasted light enough that people noticed. By 2010 The Barn was pouring single origins on Auguststraße with a list of rules on the door, Five Elephant was baking cheesecake next to its espresso in Kreuzberg, and Coffee Circle was selling direct-trade Ethiopian coffee by subscription.

Fifteen years on, the rules relaxed and the scene spread. Berlin has no centre, and the coffee follows the city's shape: showcase cafés in Mitte, courtyard roasteries in Kreuzberg's brick Gewerbehöfe, a zero-waste café in Neukölln, and the big machines out in Wedding, Tempelhof and Marzahn where the rents and the ventilation are easier. A shared roastery in Wedding lets a dozen small brands roast on industrial machines they could never buy.

The scene is international in the way Berlin is. The Barn has flagships in Seoul and Dubai, Bonanza ships to Korea, the counters work in English as often as German, and the national barista champions keep coming out of the training rooms at Röststätte. In autumn, Coffee Week Berlin spreads the festival across the whole city instead of one hall.

The pioneers are still the reference points. Bonanza roasts light in a Kreuzberg brick factory and runs four cafés from Prenzlauer Berg to Gendarmenmarkt. The Barn roasts only single origins that clear its own cupping bar, from a Wedding factory with a bakery attached, and sells them from Seoul to Mallorca. Five Elephant pairs direct-trade Colombians and Brazils with a cheesecake that has its own following. 19grams roasts at Alexanderplatz, runs public cuppings every week and pours in four cafés. Coffee Circle roasts organic direct-trade lots in Wedding and sells most of it by subscription.

The second ring is wide. Röststätte roasts on hot-air machines in Mitte and trains champions upstairs. Fjord roasts Scandinavian-light in Marzahn for cafés across Europe. Flying Roasters

Berlin has no centre and neither does its coffee. Six zones, each with its own job.

A flat white or a filter, and very often with oat milk, which is on every bar and frequently costs nothing extra. Most roaster-cafés run two grinders, one for the house espresso and one for a bright single origin, and a batch brewer for the queue. On the shelf, Colombia, Ethiopia and Brazil lead Berlin's listed origins, washed leads the processes with natural behind it, and the roasters return year after year to the same valleys: Guji and Yirgacheffe, Huila and Tolima, Tarrazú.

The roast is lighter here than almost anywhere in Germany, though the early dogma has softened: The Barn and Fjord still roast Nordic-light, while much of the city now roasts a little longer so the coffee works in the automatic machines Berliners have at home. Anaerobic, yeast-fermented and thermal-shock lots have moved from the cupping table to the retail shelf. Decaf has lost its stigma, with sugarcane-process and water-process lots priced like any other coffee. The live count stands at 26 decaf and 87 filter-friendly listings.

Berlin's roasters print farm-gate prices and cupping scores on the bag, so the ladder is unusually transparent. These numbers come from every Berlin coffee currently listed with a price, not a sample we chose. The going rate today is €56 per kilogram, about €14 for a standard bag.

The ladder reads like this: house espresso blends and washed Latin Americans around €42 per kilogram, washed East Africans and the first experimental lots from about €68 per kilogram, and the most expensive listing right now at €333 per kilogram. 297 coffees carry a price today. Nearly every roaster here sells online and by subscription, and the bigger ones ship across Europe.