HMS Queen Elizabeth has been floated for the first time at docks in Rosyth this morning at 3am.
The giant aircraft carrier is the largest warship ever built for the Royal Navy and was formally named by the Queen in a ceremony earlier this month.
It will remain in Rosyth until it is handed over to the Ministry of Defence in 2016 ahead of being put into service in 2020.
The warship is as long as 25 buses and can carry 40 jets and helicopters at a time.
It will have a permanent crew of almost 1,600.