AIDIN, or Guzel-Hissar, a town of Turkey in Asia, in the pashalic of Anatolia, about 70 miles S.E. of Smyrna. It is beautifully situated near the river Meander, and is the residence of a pasha. Since 1866 it has been connected with Smyrna and Ephesus by rail. On a neighbouring height are to be seen the ruins of the ancient Tralles. Aidin is a place of very extensive trade, and is celebrated for its figs, which are grown in great abundance in the beautiful orchards between the town and the river, and form an important article of export. The streets of the town, overshadowed by trees, and having numerous well-frequented bazaars, present a very picturesque appearance. Among the inhabitants are considerable numbers of Greeks, Armenians, and Jews; and there are several churches and synagogues in addition to the fine Turkish mosques. Population, 30,000.