The sturdy Airedale is the largest of all terriers. Males stand about 23 inches at the shoulder; females are a bit smaller. The wire coat is tan with dark markings. Rangy but muscular legs give Airedales a regal lift in their bearing, and the long head—with its sporty beard and mustache, expressive eyes, and neatly folded ears—conveys a keen intelligence. Airedales are the picture of an alert and willing terrier—and then some.