The cave wolf (Canis lupus spelaeus ) is an extinct subspecies of wolf that lived during the Late Pleistocene Ice Age. It inhabited what is now modern-day western Europe. The Don wolf (C. l. brevis ) from eastern Europe is regarded as a taxonomic synonym, which indicates that one subspecies once lived across Europe.
Cave wolf populations are known from three caves separated by a few kilometers from each other that are located on the Franconia Karst along the Wiesent and Ahorn River vallies in the Upper Franconia region of the state of Bavaria, Germany. Sophie's Cave sits on the northwest slope of the Ailsbach Valley near Rabenstein Castle in the Ahorntal municipality. Große Teufels Cave (Big Devil's Cave) and the Zoolithen Cave are located nearby. They are also known from Hermann's Cave in the village of Rübeland near the town of Wernigerode, in the district of Harz, Saxony-Anhalt, Germany. Its bone proportions are close to those of the Canadian Arctic-boreal mountain-adapted timber wolf and a little larger than those of the modern European wolf. Some postcranial bones have similarly large proportions to those from the Sophie's and Große Teufels Caves, where the bone sizes are closer to those of Scandinavian Arctic and Canadian Columbian wolf subspecies than to those of the smaller European wolves. Bone sizes are one-eighth larger than European wolves, and this wolf was a specialized Late Pleistocene wolf ecomorph.