Some of the world's prettiest dogs gathered at the annual Westminster Kennel Club dog show in the U.S. to win the title of best of their breed. /VCG Photo

The show returned to New York City for the 143rd time on Monday, when 2,800 elite dogs competed for the Best in Show title. This year’s show ran from Monday to Tuesday and was available to live stream online. /VCG Photo

Dogs in all breeds went head-to-head in seven groups: toy, non-sporting, hound, terrier, herding, sporting and working. The winner of each group then advanced to the Best in Show competition. /VCG Photo

Owners ran their dogs on the playground during the breed judging. /VCG Photo

The first Westminster Kennel Club Dog Show was held on May 8, 1877, making it the second-longest continuously held sport event in the U.S. after the Kentucky Derby, which started in 1845. /VCG Photo