Jopen

Haarlem cared enough about its beer to write the recipe into the public record, and in 1407 the city's bierkeur — its beer ordinance — specified a mash of barley, wheat and oats bittered not with hops but with gruit, a herb mixture dominated by sweet gale. Jopen went into the municipal archives, found it, and brewed it. That beer is Koyt, and it is the only traditional gruit recipe still in production anywhere: every other gruit beer on the market is a reconstruction or an invention. The brewery works out of a converted church, the Jopenkerk, which is the detail everyone mentions — but the archive is more interested in the fact that a fifteenth-century town clerk is the reason the recipe exists at all.

Sources

1. recordConfirmed

   Koyt is brewed from the 1407 bierkeur, the Haarlem city beer recipe preserved in the municipal archives — a gruit beer bittered with a herb mixture dominated by sweet gale rather than hops, and the only traditional gruit recipe surviving in production. This corrects an earlier entry describing it as a 14th-century recipe; 1407 is the 15th century.

   Jopen and the 1407 Haarlem bierkeur · Reference and brewing sources, cross-checked · 2026

   ReferenceMedium reliabilityAccessed 2026-08-20Reviewed 2026-08-20
2. foundedDisputed

   Founding year DISPUTED. The Stichting Haarlems Biergenootschap, the beer society behind the revival, was established in 1992; the Jopen brewery itself is dated to 1996. This record holds 1994, which is unsourced and matches neither. All three are recorded and none is chosen.

   Jopen and the 1407 Haarlem bierkeur · Reference and brewing sources, cross-checked · 2026

   ReferenceMedium reliabilityAccessed 2026-08-20Reviewed 2026-08-20

Only the claims above are sourced. Everything else on this page is the archive's own research and has not yet been tied to a document — which is worth knowing rather than hiding.