- The Indian Navy observes December 8 every year as the Submarine Day to commemorate the foundation day of the Indian Navy’s Submarine Arm.
- The day marks the induction of the first submarine, “INS Kalvari (S-23) into the Navy in 1967.
- INS Kalvari (S-23) – a Foxtrot class submarine was de-commissioned after 29 years of service on 31 May 1996.
