The aft island of the double island 'HMS Queen Elizabeth' has been lowered into place by Aircraft Carrier Alliance workers at Rosyth Dockyard in Fife.
After an air horn sounded, a huge Goliath crane was used to lower the 750-tonne section of the aircraft carrier, known as Upper Block 14, into place.
HMS Queen Elizabeth and HMS Prince of Wales promise to be the biggest and most powerful surface warships ever constructed for the Royal Navy.
Programme Director Ian Booth said:
"Moving this section into place is a momentous occasion for the programme. HMS Queen Elizabeth now has a completely unique and distinctive profile and, thanks to the dedication of thousands of workers, just a few sections remain to be assembled. She will be structurally complete by the end of this year."
The aft island was the final section of HMS Queen Elizabeth to arrive at the Rosyth assembly site and was constructed in 90 weeks by workers at BAE Systems’ yard in Scotstoun.
HMS Queen Elizabeth is the first aircraft carrier to use an innovative design of 2 islands. The forward island, which has already been erected, houses the ship’s bridge, while the 30-metre-tall aft island will house the air traffic control equipment, making it the centre of all onboard flight operations.
Rear Admiral Steve Brunton said:
"HMS Queen Elizabeth will be at the centre of the UK’s defence capability for the 50 years she is expected to be in service.
She will be absolutely unique and, combined with assets across the rest of the UK’s Armed Forces, will provide this country with an unprecedented level of capability, protecting UK interests and providing humanitarian support across the globe."
Apprentice Gordon Currie, who operated the horn which marked the start of the manoeuvre to lower the island, said:
"It is a huge honour to sound the horn and signal the final stage in the lift. I am just one of hundreds of workers working on this incredible ship, and it is something I will always be really proud of."