High Quality Content by WIKIPEDIA articles! The Draining of the Mesopotamian Marshes occurred in Iraq and to a smaller degree in Iran between the 1950s and 1990s to clear large areas of the marshes in the Tigris-Euphrates river system. Formerly covering an area of around 20,000 km2 (7,700 sq mi), the large complex of wetlands was 90% drained prior to the 2003 Invasion of Iraq. The marshes are typically divided into three main sub-marshes, the Hawizeh, Central, and Hammar Marshes and all three were drained at different times for different reasons. Initial draining of the Central Marshes was intended to reclaim land for agriculture but later all three marshes would become a tool of war and revenge.