Simplify the following text for a Grade 12 native English-speaking person.
Original: All that remains of the original ancient famed city of Babylon today is a mound , or tell , of broken mud-brick buildings and debris in the fertile Mesopotamian plain between the Tigris and Euphrates rivers .
Simplified: All that remains of the original ancient famed city of Babylon today is a mound of broken mud-brick buildings and debris in the fertile Mesopotamian plain between the Tigris and Euphrates rivers .