Brouwerij Cornelissen is a historic family brewery located in Opitter, in the Belgian province of Limburg. Its roots stretch back to the first half of the nineteenth century, with the brewery officially founded in 1859. What began with Jan Mathys has since grown into a six-generation family business, making Cornelissen one of the most enduring craft breweries in Belgium. The family name on the label is not just a brand — it is a statement of heritage and commitment. The brewery produces a wide and diverse portfolio of around 17 different beer styles, ranging from pilsners to more complex specialty beers. Among their notable lines is the Herkenrode series, which includes beers such as the Herkenrode Vesper and Herkenrode Noctis — names that reflect the region's rich monastic and cultural history. Another standout is the Ops-Ale, a pils that earned recognition at the Brussels Beer Challenge. The brewery also brews beers tied to historical themes, including a range referencing the end of the First World War. Brouwerij Cornelissen has built a strong international reputation, with exports reaching markets including Russia and India, and appearances at international beer competitions and tastings. Visitors are welcome at the active brewery, where the full brewing process can be experienced firsthand. The brewery has received recognition at multiple international beer competitions.