When Istanbul chose a new mayor in March, Turkey’s president described the vote as a matter of national survival.
But the ruling party’s candidate was narrowly defeated and the new mayor, Ekrem Imamoglu, took office.
After a successful court challenge, the election was annulled and a rerun declared. Turks are now facing a dramatic second vote on Sunday.
Presenter: Beril Akman. Video by Ilgin Karlidag, Suniti Singh, Paul Brown and Pinar Ersoy.
Istanbul vote: Why rerun vote is key to Turkey’s future