Indian Navy Day is celebrated on December 4 in commemoration of Operation Trident, the attack launched by the Indian Navy on Karachi harbour during 1971's Indo-Pakistan war. It was for the first time that an anti-ship missile was used in the operation. The operation was conducted on the night of December 4-5 and it inflicted heavy damage on Pakistani vessels. India did not suffer any loss during the operation.
As part of the operation, the Indian Navy sank four Pakistani vessels and ravaged Karachi harbour fuel fields in Pakistan.
The Indian Navy's three warships -- INS Nipat, INS Nirghat and INS Veer -- played an important role in the attack.
The Indian Navy fleet sailed from Gujarat's Okha Port towards Pakistani waters to attack the Karachi port. The fleet reached 70 miles south of Karachi at night and after missiles were fired Pakistani vessel -- PNS Khaibar-- sunk.
Many Indian Navy personnel who were part of the successful operation were honoured with gallantry awards.
The Indian Navy is the marine branch of the Indian Armed Forces and the President of India is its Commander-in-Chief. Chhatarpati Shivaji Bhosle, Maratha emperor, is considered as 'Father of the Indian Navy'.
Indian Navy Day is also celebrated each year to work towards securing marine borders and bolstering relationships with other countries through joint exercises, humanitarian missions and relief operations.
The Navy also organises a Beating Retreat ceremony at Gateway of India in Mumbai on the eve of the Navy Day. The Indian Naval Band performs across places between Gateway of India and Radio Club in Mumbai. The Indian Navy warships and aircraft are open to visitors, especially school children.