Brouwerij Martinus crafts an unconventional bottom-fermented lager in the heart of Groningen, drawing inspiration from classical lager traditions. The Lager der A is unfiltered and unpasteurized, preserving the character of an authentic local house beer.

This is a notably hoppy lager with a modest 4.2% ABV. The name references the Aa river that flows through Groningen and forms part of the brewery's strong local identity. Brewed with care and precision, it represents a return to how lagers were once made and enjoyed in neighbourhood bars.