Sonepur is best known for one of the largest cattle fairs that is held here every year. The Sonepur Cattle Fair or Sonepur Mela is held on Kartik Poornima (the full moon day) in the month of November in Sonepur, Bihar, on the confluence of river Ganga and Gandak. It has its origins during ancient times. The Sonepur Cattle Fair once used to attract traders from places as distant as Central Asia.

Nearly all animals can be bought at the Sonepur mela from all breeds of dogs, camels, buffaloes, donkeys, ponies, monkeys, chimps, Persian horses, sheep, rabbits, bears, cats, and guinea pigs. All varieties of birds, poultry and fishes are also available. The area that attracts all, however, is the sight of numerous elephants, beautifully decorated for the purpose of sale.. The Sonepur Fair is the only one where such a large number of elephants are sold.

Numerous stalls are also set up at the grounds of the Sonepur Cattle Fair. You will find a wide variety of goods in these stalls, ranging from garments, to weapons and furniture, toys, utensils and agricultural implements, jewelry and handicrafts.