Which breed is the largest of the terrier breeds?

The Airedale Terrier is the largest of the terrier breeds.

Often called the “King of Terriers,” the Airedale originated in Yorkshire’s Aire Valley during the 19th century. Breeders developed it by crossing the old Black and Tan Terrier with the Otterhound and probably other local terriers. The result was a versatile working dog able to hunt otters, control vermin, guard farms, and retrieve game.

Its size helped distinguish it from smaller terriers such as the Scottish, Welsh, and Irish Terriers. Airedales typically stand about 22–24 inches at the shoulder and have a muscular, athletic build, though unusually large lines have also existed. The breed’s wiry black-and-tan coat is another familiar hallmark.

The Airedale was later used as a police dog, messenger, guide dog, and military dog, especially during World War I. “Largest” refers to the terrier group rather than all dog breeds: the Airedale is substantial for a terrier but is much smaller than giant breeds such as the Mastiff or Great Dane.