Cairn Terriers are active, alert, intelligent, and independent. Their hunting ability including their keen sense of smell allows them to participate in earthdog trials. Other hunting-related behaviors include barking and scratching at the ground or digging; however, the dog's having an acceptable location for digging such as a sandbox or mulch bed can minimize the impact of this behavior. Other traits derived from the breed's hunting background that can impair a Cairn Terrier's bond include chasing wildlife and being difficult to disengage from an activity or behavior.
The Cairn Terrier dates back to the sixteenth century, although the first public presentation of the breed was not performed until 1909. The Cairn Terrier originated on the Isle of Skye in Scotland. They were originally bred to hunt smaller animals, such as foxes, weasels and rodents. Once known as the Short-Haired Sky Terrier, the name "Cairn Terrier" wasn't actually implemented until 1912. The name "Cairn" originated from rock formations in Scotland used to mark land boundaries and burial sites. The Cairn Terrier oftentimes hunted the vermin that would infest the formations. The breed was brought to the United States in 1913 and it didn't officially receive American Kennel Club recognition until 1938. The best known Cairn Terrier in the United States to date is Toto, from the 1939 film The Wizard of Oz. Identification of the state of Kansas with the original story led a resident of Wichita, Kansas to start a movement to make the Cairn Terrier the official dog of the State of Kansas.