While you would ordinarily expect a lawsuit between citizens of country A regarding the ownership of property in Country A would be venued in Country A, this is not necessarily true where Country A happens to be Iran.
In Aghaian v. Minassian, 14 C.D.O.S. 1594, plaintiffs are heirs of Gagik Galstian and Knarik Galstian who owned a number of properties in Iran but were forced to abandon them in 1978 when the family fled to Los Angeles after the overthrow of the Shah. Plaintiffs are women and non-Muslim.