Indian Navy Day is observed on December 4 every year to celebrate the success of the Indian Navy and salute the valour and courage of the naval personnel. Also known as ‘Navy Day’, various events including open sea swimming contests are organized by the Indian Navy on this day. Notably, the day is always celebrated with a different theme every year. December 4 was chosen as on that day in 1971, during Operation Trident, the Indian Navy sank four Pakistani vessels including PNS Khaibar, killing hundreds of Pakistani Navy personnel. On the day, those killed in the Indo-Pakistan War of 1971 are also remembered