Cheshmeh-Ali (meaning:Ali's spring) is a natural and swimming spring in Rey in Iran. The spring is located in south of Tehran. Cheshmeh-Ali is run from a big rock and flown to south-east. Cheshmeh-Ali dates back 8000 years ago and is placed under Rey Castle. Inscription of Fath Ali Shah is between Rey Castle and Cheshmeh-Ali from top to down. 