Water is a deeply precious and historically managed resource in Iran, defining both its ancient agriculture (via *qanats*) and modern geography.
* **Caspian Sea & Persian Gulf:** Iran is bordered by the Caspian Sea (the world's largest inland body of water) to the north, and the strategically vital Persian Gulf and Gulf of Oman to the south. * **Rivers:** The **Karun River** is Iran's most effluent and only navigable river. The **Zayanderud** in Isfahan is culturally iconic, though it frequently runs dry today due to drought and water management issues. * **Lakes:** **Lake Urmia** in the northwest was once one of the world's largest saltwater lakes. Though it has severely shrunk due to climate change and damming, extensive restoration efforts are ongoing. * **Waterfalls:** The Zagros and Alborz mountain ranges hide numerous spectacular waterfalls, such as Margoon Waterfall in Fars province.