About 15 to 20 canine wave riders are set to vie for top dog in the World Dog Surfing Championships outside San Francisco this weekend.

The dogs will vie for the title in the annual competition near San Francisco, watched by thousands of spectators.

About 15 to 20 canine wave riders are set to vie for top dog in the World Dog Surfing Championships outside San Francisco this weekend.

About 15 to 20 canine wave riders are set to vie for top dog in the World Dog Surfing Championships outside San Francisco this weekend.