There's no share land between these two countries.
They only have a long border of some 2000 kilometers
The Shatt al-Arab and its Iranian counterpart known as Khuzestan were the main pieces of land disputed between Iran and Iraq.
Iran's border with Iraq is longer than any other single border that Iraq has with any other nation, Syria included. However, the border between Iraq and Iran is less than 40% of all Iraqi land borders.
Iran and Iraq are on the eastern side of the Middle East and form the land that bridges Turkey, the Levant, and the Arabian Peninsula in the west and the Indian Subcontinent and the Stans in the east.
Iran > Iraq > Israel.
Iran, Iraq, Turkey, Syria, Isreal, Jordan, Lebanon and many other countries control land that used to be the Persian Empire.
Iraq was trying to acquire the oil-rich Iranian province of Khuzestan which has an Arab ethnic majority. Iran invaded Iraq in response with no particular piece of land in mind.
Iran.
Iran never looked after Iraq.
Former name of Iran: PersiaFormer name of Iraq: Mesopotamia
Mesopotamia is located in present-day Iraq
Iraq and Iran were parts of Persia
Iraq