Sonepur Cattle Fair (Hindi: सोनपुर पशु मेला) is held on Kartik Poornima (the full moon day) over the months of November and December in Sonepur, Bihar, on the confluence of river Ganges(Gandak). It is also known as Harihar Kshetra Mela. To date, it is the biggest cattle fair in Asia and usually lasts from between fifteen days to one month in duration. It was historically started during Vedic period. The Sonepur Cattle Fair used to attract traders from places as far away as Tamil Nadu and Delhi. In 2018, the Fair started on the 21st of November and continued until the 22nd of December.