Radlermass (translated: “cyclist’s litre”;”mass” is an old Bavarian word for “litre”) is a mixed beer-based drink with a long history in German-speaking regions. Its northern German name is “Alsterwasser.” Usually consisting of a 50/50 mixture of various types of beer and German-style clear lemon-lemonade, the invention of the Radler has been widely attributed to the Munich gastronomer Franz Xaver Kugler in 1922. Radlermass is the Bavarian equivalent of the British shandy (which is also a mixture of beer and lemonade, or, less often, ginger beer). Kugler’s “cyclist’s litre” became very popular in Munich, and other beer gardens offered the same mixture.
Today radler is not only drunk in Bavaria but all across Germany and Austria. In Austria it is usually a mixed beer with cloudy orange-lemonade. During the summer months, radler is very popular because of its reputation for being a perfect thirst-quencher – a result of its harmony in sweet-bitter and sour taste – and is bottled premixed and available all over Germany. Until the 1990s in Germany it was forbidden by law to produce radler in bottles (it had to be mixed in the beer garden by adding half a litre of lemonade to half a litre of beer), but nowadays the market share of ready-mixed radler and other beer-based drinks is increasing.
The “Russenmass” is a mixture of hefeweizen and lemonade. The “Diesel” is a mixture of lager and a cola-based beverage. The mixing of these two drinks produces a diesel-fuel-like colouration, which explains the name of the drink. There exist several regional differences in names and variants. Hefeweizen mixed with cola is called a “Colaweizen.” Weißbier mixed with cola is called a “Flieger” (“Aviator”), or “Turbo.” Pilsner or altbier and cola are known as a “Krefelder.”
Stempfl, Wolfgang (2011) Radlermass. The Oxford companion to beer, 1, 686.
In New Zealand, the term “radler” was trademarked in 2003 by DB Breweries.