Sadarak District () is one of the 7 districts of the Nakhchivan Autonomous Republic of Azerbaijan. The district borders the district of Sharur, as well as the Iğdır Province of Turkey, Ararat Province of Armenia and the West Azerbaijan Province of Iran. Its capital is Heydarabad and largest settlement is Sadarak. As of 2020, the district had a population of 16,100. Sadarak is the only Azerbaijani district bordering Turkey. The Umut Bridge over the Aras, also called the "bridge of hope", links Azerbaijan with Turkey, where the Nakhchivan-Istanbul bus route passes. Sadarak District also includes the Karki exclave which has been controlled by Armenia since the First Nagorno-Karabakh War. Etymology There are different theories about the word's origin. Some say Sadarak means three valleys in Farsi. Indeed, there are three valleys in Sadarak: Chanagchichay, Chahannamdara, Bagirsag. Linguists link the word to "sed rang", i.e. a hundred colours. Sedrak means a place inhabited by many people in Arabic. In the 14th century, it was inhabited by the Saadli tribe. Local etymology suggests that Sadarak is made up of steel and garak (flood-prone). Researchers believe that the word relates to a place called Sakrak mentioned in the Book of Dede Korkut. History The Barda-Erevan-Nakhchivan-Julfa-Tabriz section of the Great Silk Way linking Azerbaijan's north with Middle Eastern countries passed through Sadarak. During the 1722 attack of Peter the Great on the Caucasus, including Azerbaijan, Nakhchivan fell under the influence of the Ottomans, while following the 1828 Turkmenchay agreement it was passed on to Russia to become part of Erevan province. In a letter to Gen Paskevich from 23 September 1828, A. Griboyedov provided information about the Nakhchivan population. Under the 1828 decree of Czar Nicolas the First, the Armenian Oblast was established in part of the Armenian Highlands, on the territory of the former Erivan and Nakhchivan khanates; about 130,000 Armenians resettled there to their former homes from Iran and Turkey. 31 December 1989 saw an extraordinary event in USSR history as state borders called "the metal grating" were knocked down enabling people to cross the Aras. In early 1990, the Supreme Council of the Nakhchivan SSR passed a shocking decision to secede from the USSR. Proceeding from the Kars agreement, the autonomous republic's legislature asked Turkey, Iran, the UN and other international organizations for help. The decision came like thunder from a clear sky. It was the first time in USSR history