Yerevan (sometimes spelled Erevan, Erivan, Jerewan, Jerevan, etc.) has a long-long history of thousands of years, dating back to the rise of oldest civilizations in the world.
The territory of Yerevan was settled by humans since the 4th millennium BC, fortified settlements from the Bronze Age include Shengavit, Karmir Blur, Karmir Berd and Berdadzor. Archaeological evidence indicates that an Urartian military fortress called Erebuni (Էրեբունի) was founded in 782 BC by the orders of King Argishtis I at the site of current-day Yerevan, to serve as a fort/citadel guarding against attacks from the north Caucasus, thus Yerevan is one of the most ancient cities in the world. Irrigation canals and an artificial reservoir were built on the territory of Yerevan during the height of Urartian power. The fortress of Teishebaini (Karmir Blur) was destroyed by the Scythians in 585 BC. Between the 6th and 4th centuries BC, Yerevan was one of the main centers of the Armenian satrapy of the Achaemenid Empire. The timespan between 4th century BC and 3rd century AD is known as the Yerevan Dark Ages due to absence of historical data. The first church in Yerevan, the church of St. Peter and Paul was built in the 5th century (collapsed in 1931).
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During the height of the Arab invasions, Yerevan was taken in 658 AD. Since then the site has been strategically important as a crossroads for the caravan routes passing between Europe and India. It has been called Yerevan since at least the 7th century A.D. Between the 9th and 11th centuries Yerevan was a safe part of the Armenian Bagratuni Kingdom, before being overrun by Seljuks. Yerevan was seized and pillaged by Tamerlane in 1387. The city became an administrative center of the Ilkhanate. Due to its strategic significance, Yerevan was constantly fought over and passed back and forth between the dominion of Persia and the Ottomans for centuries. At the height of Turkish-Persian wars, the city changed hands 14 times between 1513 and 1737. Under the order of Shah Abbas I tens of thousands of Armenians, among them citizens of Yerevan, were deported to Persia in 1604. As a direct result of those deporations, the Muslims made up 80 percent of the new population of Yerevan, while native Armenians constituted the remaining 20 percent of the population. Jean Chardin, a French traveller, visited Yerevan and gave a description of the city in his Travels of Cavalier Chardin in Transcaucasia in 1672-1673. On June 7, 1679, a devastating earthquake razed the city to the ground. It is of interest to note that Ottomans, Safavids and Ilkhanids all maintained a mint in the city of Yerevan.
Yerevan was liberated by Russian troops under Ivan Paskevich during the second Russian-Persian war on 1 October 1827 and formally ceded by the Persians in 1828. Following the Treaty of Turkamanchai, tsarist Russia sponsored Armenian resettlement from Persia and Turkey, the Armenian population rose and by the turn of the 20th century the population of Yerevan was 29 033 and consisted of Russians — 2%, Armenians — 48% and Azerbaijanis (called Azerbaijani Tatars by contemporary Russian sources) — 49%. The city started to grow economically and politically. Old buildings were torn down and new buildings of European style were erected. In 1829 Armenian repatriates from Persia were resettled in the city and a new quarter was buit. By the 1830's, Yerevan was an uezd. Emperor Nicholas I visited Yerevan in 1837. The first general plan of the city was made in 1854. Between 1850 and 1860, the female colleges of St. Hripsime and St. Gayane were opened and the English Garden was built. The first printing house of Zacharia Gevorkian was opened in 1874 and the first theatre was built in 1879 near the church of St. Peter and Paul. Yerevan was connected via a railway line to Alexandropol, Tiflis and Julfa in 1902, in the same year the first public library was opened. A telephone line with 80 subscribers was put into operation in 1913. The October Revolution in 1917 put an end to the Russian Empire. The Armenian, Georgian and Muslim leaders of Transcaucasia united to form the Transcaucasian Federation, which officially proclaimed the secession of Transcaucasia from the Russian Empire.
After the Russian Revolution of 1917, the city passed into the control of the Transcaucasus interim government which was established, in the spring of 1918 as the short-lived independent Transcaucasian Federation with the capital in Tbilisi. On May 28, 1918, Yerevan became the capital of the independent First Republic of Armenia. On 29 November 1920 the 11th Red Army, invaded Yerevan and established the Soviet regime. In February 1921 nationalist forces managed to retake the city briefly but on April 2, 1921 Bolsheviks retook the city.
Yerevan became the capital of the newly formed Armenian Soviet Socialist Republic, one of the 15 republics of the Soviet Union. The Soviet era transformed the city that was originally intended for a few thousand residents into a modern metropolis with over a million people, developed according to the prominent Armenian architect Alexander Tamanian’s design. Tamanian successfully incorporated national traditions with contemporary urban construction. The design presented a radial-circular arrangement, most appropriate for the local relief that has since become one of the main attractions of the city. Tamanians new layout for the city was imposed over the existing old city - which led to the destruction of a large number of buildings of historic importance. Important churches, mosques, the Persian fortress, baths, bazaars and caravanserais were all demolished during the Soviet period. The city was transformed into a large industrial, cultural and scientific center; with over 200 important industrial enterprises. During the commemoration of the 50th anniversary of the Armenian Genocide, Yerevan was the center of a 24 hour mass anti-Soviet protest (the first such demonstration in the USSR) to demand recognition of the Armenian Genocide by Soviet authorities. In 1968 the city's 2750- anniversary was commemorated. The city became one of the largest industrial and cultural centers of the Soviet Union. In 1981 the first stations of the Yerevan Metro opened. In 1988-1989 the whole Azerbaijani population of Yerevan was expelled from the city 
Yerevan is located in Eastern Armenia in the North-Eastern part of the Ararat Valley. The upper part of the city is surrounded by mountains on three sides while to the south it descends to the banks of the river Hrazdan, a tributary of the river Arax that divides the city into two within a picturesque canyon. The elevation of the city ranges between 900 to 1,300 meters over the sea level, displaying a 400 meter disparity between its lowest and highest points.
As the capital of Armenia, Yerevan is not part of any marz. It borders the following marzer: Kotayk (north), Ararat (south), Armavir (southwest) and Aragatsotn (northwest).
The climate of Yerevan is relatively continental with a dry, hot summer and a cold and short winter. The temperature of the hottest month of August reaches to 40 degrees Celsius and the coldest month of January to -15 degrees Celsius. The amount of precipitation is small and amounts to annually to about 350 mm.