The strongest tier of Belgian abbey-style ales — deep amber to dark brown, typically 9–12%+ ABV, with intense dark fruit, caramel, toffee, and rich Belgian yeast complexity. La Trappe Quadrupel (1991) coined the ‘quadrupel’ name commercially, though Trappistes Rochefort 10 is an often-cited point of comparison for the profile.
In the glass
Origin
The “quadrupel” name was coined in 1991 by the Dutch Trappist brewery La Trappe (De Koningshoeven) for the strongest beer in its lineup, launched at around 10% ABV. It was the first beer to carry the name commercially, and the term has since become a generic descriptor for an especially strong dark abbey-style ale, particularly in the United States. Rochefort 10, the strongest expression from the Belgian Trappist brewery at Rochefort, is a comparably strong Trappist dark ale that resembles the quadrupel in strength and dark-fruit profile, though Rochefort does not itself use the “quadrupel” label. The category is now well established worldwide.
Notes
Despite the name’s tidy numerical logic, “quadrupel” does not denote a beer brewed at exactly four times any base strength; it follows the loose Belgian convention of naming beers with ascending numbers to suggest relative potency, the same convention behind dubbel and tripel. In Belgium, comparable strong dark ales are often labeled “grand cru” rather than “quadrupel.” The strongest Trappist and abbey dark ales — Rochefort 10, St. Bernardus Abt 12, Westvleteren 12 — sit in this territory whether or not they carry the word on the label.
Defining examples
La Trappe Quadrupel·Trappistes Rochefort 10·St. Bernardus Abt 12·Westvleteren 12·Ommegang Three Philosophers