Turkish President Recep Tayyip Erdogan is planning a massive rally in Istanbul on Sunday, which authorities claim will be attended by 1 million people, to mark the 563rd anniversary of the Ottoman conquest of Constantinople from the Byzantine Empire.
The event will be attended also by Binali Yildirim, the new head of the ruling Islamic-rooted Justice and Development Party (AKP) and prime minister-designate, according to the mayor's office.
The air force will make a show of strength, doing a fly-past, and 563 people dressed in janissary costumes will perform. A 3D mapping of the city as it was in 1453 will also be presented.
Security measures are expected to be tight ahead of the event, which the government is advertising heavily, in a large-scale marketing blitz, using images of Sultan Mehmet the Conqueror and pictures of the president. Erdogan last year used the anniversary, which came just ahead of a crucial election, to attack critics.
In recent weeks, he has been pushing for constitutional changes to empower his office, worrying the opposition, which fears this will erode checks and balances, amid existing accusations of growing authoritarianism.