Chehel Dokhtar Tower, Semnan
This tower is located in the Hakim Ellahi Avenue of Semnan. The people of Semnan believe that 40 girls who were recluses constructed this tower with sun baked bricks and clay. The construction of the same is related to the pre- Islamic era. This tower is octagonal and has an elevation of 10 - 12 m. and the thickness of its walls approximately 50-60 cm. Due to the expansion of the city the said tower is now located in the midst of a play-ground of a school.