Remarkable too are the two octagonal tomb towers in Kharraqan, some 300 km south-east of Marragha. On both building date and name of the architect is written, the same one for both towers. The walls and accentuated columns at the corners are completed covered by geometric pattern. Remarkable is the fact that some joint are in flush with the outer wall, while other lie deeper in the wall exploiting effects of light and shadow. The eastern tower dates from 1068 and bears more than 30 different patterns. The tympan above the entry bears a geometric pattern of intertwined lines. In it we see 12-pointed stars with in them the name of Allah. 100 years before the Gonbad-e Kabud you already see a polygon pattern with lines drawn at the edges producing a line pattern.