Vaisakhi (Punjabi: ਵਿਸਾਖੀ, Hindi: बैसाखी vaisākhī, also known as Baisakhi or Vasakhi) is an ancient harvest festival in the Punjab region, which also marks beginning of a new solar year, and new harvest season. Baisakhi is a Sikh religious festival. It falls on the first day of the Baisakh month in the solar Nanakshahi calendar, which corresponds to April 13 in the Gregorian calendar.
In Sikhism, it is one of the most significant holidays in the Sikh calendar, commemorating the establishment of the Khalsa at Anandpur Sahib in 1699, by the 10th Sikh Guru, Guru Gobind Singh.
This day is also observed as the beginning of the Hindu solar new year celebrated by the people of Nepal and India in Assam Valley, Kerala, Orissa, West Bengal and some other regions of India. The particular significance attached to the occasion shows regional variation outside of Punjab too. In Himachal Pradesh, the Hindu Goddess Jwalamukhi is worshipped on Vaisakhi, while in Bihar, the Sun-god Surya is honoured. The festival is celebrated as Rongali Bihu in Assam, Naba Barsha or Pohela Boishakh in Bengal and Tripura, Puthandu (Tamil New Year) in Tamil Nadu, Vishu (or Vaishakhi) in Kerala, Bikhu or Bikhauti in the Kumaon region of Uttarakhand, Maha Vishuba Sankranti (or Pana Sankranti) in Orissa, and the Sinhalese New Year festival in Sri Lanka. Besides in Punjab, Baisakhi is widely celebrated as a traditional harvest festival in many northern states of India, such as Haryana, Himachal Pradesh and Uttarakhand. In many places the day is marked by ritualistic bathing in sacred rivers like the Ganges.