|Location||Al-Warka, Muthanna Governorate, Iraq|
|Area||6 km2 (2.3 sq mi)|
|Founded||4th millennium BC|
|Abandoned||Approximately 700 AD|
|Periods||Uruk period to Early Middle Ages|
|Official name||Uruk Archaeological City|
|Part of||Ahwar of Southern Iraq|
|Inscription||2016 (40th Session)|
|Area||541 ha (2.09 sq mi)|
|Buffer zone||292 ha (1.13 sq mi)|
Uruk (//; Cuneiform: 𒌷𒀕 or 𒌷𒀔 URUUNUG; Sumerian: Unug; Akkadian: Uruk; Arabic: وركاء or أوروك, Warkāʼ or Auruk; Aramaic/Hebrew: אֶרֶךְ ʼÉreḵ; Ancient Greek: Ὀρχόη, romanized: Orkhoē, Ὀρέχ Orekh, Ὠρύγεια Ōrugeia) was an ancient city of Sumer (and later of Babylonia), situated east of the present bed of the Euphrates river, on the dried-up, ancient channel of the Euphrates, some 30 km east of modern Samawah, Al-Muthannā, Iraq.
Uruk is the type site for the Uruk period. Uruk played a leading role in the early urbanization of Sumer in the mid-4th millennium BC. At its height c. 2900 BC, Uruk probably had 50,000–80,000 residents living in 6 km2 (2.32 sq mi) of walled area; making it the largest city in the world at the time. The legendary king Gilgamesh, according to the chronology presented in the Sumerian king list, ruled Uruk in the 27th century BC. The city lost its prime importance around 2000 BC, in the context of the struggle of Babylonia against Elam, but it remained inhabited throughout the Seleucid (312–63 BC) and Parthian (227 BC to 224 AD) periods until it was finally abandoned shortly before or after the Islamic conquest of 633–638.
The Arabic name of Babylonia, which eventually became the name of the present-day country, al-ʿIrāq, is thought to derive from the name Uruk, via Aramaic (Erech) and possibly via Middle Persian (Erāq) transmission.
In Sumerian the word uru could mean "city, town, village, district".