European hare adaptions for high speed running in hares include wider nostrils and larger hearts. In comparison to the European rabbit, the hare has a proportionally smaller stomach and caecum. This hare is one of the largest of the lagomorphs. Its head and body length can range from with a tail length of . The body mass is typically between . The hare's elongated ears range from from the notch to tip. It also has long hind feet that have a length of between . The skull has nasal bones that are short, but broad and heavy. The supraorbital ridge has well-developed
Swedish Hare temperament and athletic body type were paramount in developing the Elfin rabbit. Arched and muscular but large Rhinelanders were bred to the American version of the smaller Polish breed to bring the size. Other foundation stock included the Belgian Hare, the Tan, the Harlequin, the Mini Satin, and the Britannia Petite. Now that the Elfin have been included in the Swedish Hare population, an international exchange of breeding stock is possible. Though it is not the standard of the Swedish Hare, the working standard for the Elfin breed (which appears below) called for a small rabbit weighing no more than