The Tigris, with its sister the Euphrates, formed the cradle of human civilisation.  Their fertile banks and valleys formed the perfect springboard for developing centralised agricultural economies and the capacity for close proximity dwelling in large numbers.  

The Tigris commences its run to the sea as the outlet for Lake Golcuk in the Kurdish regions of Turkey.  Not far, as it happens, from where its sister emerges.  It flows southeast through fairly barren landscape along the border between Turkey and Syria before plunging straight into what is currently Iraq.  There it passes by the ruins of the capital of the Assyrian empire - Nineveh - for a distance of about 5 km.

Further on the river is joined by the Great and Lesser Zab Rivers and then enters the great Tigris-Euphrates Plain.  Here are more ruins of yet more Mesopotamian cities - the heartland of the emergent urban cultures - and the water continues to descend, south south east, to Baghdad.  From here the river sends out a branch - the Shatt al Gharraf - to join the Euphrates.  Later, at Al Qurnah, the Tigris itself joins with the Euphrates.  It is here that many believe the Garden of Eden is located.  The combined river is referred to as the Shatt al Arab as it continues the remaining 200 km through the marshy delta lands.

Tributaries
Greater and Lesser Zab

Shatt al Gharraf