The largest and most powerful ship ever built for the Royal Navy is preparing to leave her home port for the first time.
HMS Queen Elizabeth, a 280-metre, 65,000-tonne aircraft carrier is due to set out from Rosyth on the Firth of Forth on Monday, subject to final checks, tides and the Scottish weather.
The £3 billion behemoth, which is set to be the nation's future flagship, and her 700-strong ship's company, are ready to undertake her maiden sea trials over the summer.
However the vessel must first get out to sea with one of the most delicate manoeuvres of the six-week trials.
Navigators, pilots and tug boats have the slimmest of margins to deal with to guide HMS Queen Elizabeth out of the Rosyth basin where she was assembled.
At high tide the ship was taken through a narrow gate avoiding the dock walls by inches, while under the water line there was just half a metre between the bottom of the ship and the sea bed.
Commanding officer Captain Jerry Kyd said: "We have to be very careful, but you practise it and drill it and rehearse it to make sure we could do it safely in a timely fashion because the tide waits for no man."
Once in the Forth, the carrier must then wait for the tide to lower to pass under the Firth's famous bridges.
Ten thousand people worked on the construction of the ship, made up in sections at yards around the UK and transported to Rosyth where it was assembled.
The second ship in the class, HMS Prince of Wales, is being fitted out in the dock and staff will be able to look on as its sister ship sets sail for the first time.
The sea trials will take place in the North Sea before the carrier returns to Rosyth for further checks and any adjustments.
Captain Kyd said: "After that we're going back out for a further three weeks to test the ship on the more war-fighting capabilities - the radars, all the ship's sensors, radios and things like that.
"At the end of that period we know that all the basics work. She's done her test drive and after that we will go down to Portsmouth, the ship's home, and get her finally ready to join the Royal Navy fleet, hopefully at the end of the year."