TEHRAN, Dec. 11 (MNA) Forg Castle is located in Forg Village, one of the districts of Darmian town, at a distance of 90 km east of Birjand City and 10 km of Asadieh City in eastern province of Southern Khorasan. Materials used in the building include stone, brick, clay, gypsum, lime and mortar (Sarouj).