The tomb of Esther and Mordechai is located in Hamadan, Iran. Widely believed to house the remains of the biblical Queen Esther and her uncle Mordechai, it is the most important pilgrimage site for Jews in the country.
In 1891 the tomb was described as consisting of an outer and inner chamber surmounted by a dome about 50ft high. The dome had been covered with blue tiles, but most of them had fallen away.
A few tombs of worthy Jewish individuals were located within the outer chamber.[1]
According to Stuart Brown, the site is more probably the sepulcher of Shushan-Dukht, the Jewish consort of Yazdigird I (399-420 CE).
Reference: http://en.wikipedia.org/wiki/Tomb_of_Esther_and_Mordechai