'Crossing the Line' is one of the oldest traditions in the Royal Navy and takes place when a ship crosses the equator.
Royal Navy tradition dictates that any ship crossing the equator must pay its respects to the Lord of the Seas, King Neptune, to gain his acceptance.
The ceremony involves sailors being tested to ensure they are capable of 'handling rough seas' and, as per tradition, can see them being painted, fed a less than appetising snack and being dunked.
Members of crew who had never previously 'crossed the line' – and a few extras – are 'charged for their crimes' and get the justice they deserve in a somewhat comical fashion.
This rich tradition of the Crossing the Line ceremonies often involve varied events to test a seafarer who has not crossed the equator – turning them into a trusty 'Shellback' after proving themselves in front of King Neptune.
The event of Neptune's Royal Court is steeped in tradition, set rituals, grandiose speeches, elaborate costumes and props – and is usually led by King Neptune, with his consort, Amphitrite, and assistant, Davy Jones.
HMS Defender and her 180-strong crew faced King Neptune's Court this month when she marked crossing the equator, during her deployment with the Carrier Strike Group (CSG21).
The Royal Navy Type 45 destroyer shared pictures on her official Twitter account of the ceremony, including identical twins "AB(AWW) and AB(Sea) Parfitt who became Trusty Shellbacks together".
Even the Royal Navy flagship HMS Queen Elizabeth marked her first equator crossing with the traditional ceremony as she leads the CSG21 deployment.
HMS Queen Elizabeth shared pictures on her official Twitter account of the ceremony, including 'King Neptune' himself, a sailor being dunked in a pool and other personnel in outrageous costumes.
The good-humoured ceremony plays an integral role in creating a sense of community and camaraderie among a ship's company.
Crossing the Line is a rite of passage that has evolved over four centuries, and one which the Royal Navy still continues to perform today and it does not look like it is stopping anytime soon.