Radler is a German mixed beer drink made by combining beer with lemon-lime soda.
The name means “cyclist” in German. A popular origin story places the drink in Bavaria in 1922, when innkeeper Franz Xaver Kugler is said to have diluted beer with lemon soda for a large group of cyclists. The historical details of that story are debated, but the association with cycling is firmly established.
Radler is commonly made with a pale lager or wheat beer and a roughly even proportion of beer and soda, although recipes differ. It is usually lower in alcohol than the undiluted beer.
A similar drink in northern Germany is often called an Alsterwasser. Beer mixed with cola is a different style, commonly known as Diesel in Germany.