Facts

One of the most familiar landmarks of Tehran.
Included in the building is a cultural centre with a library, a museum and several art galleries.

The entrance of the tower is directly underneath the main vault and leads into the Azadi Museum on the basement floor.
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The main display is occupied by a copy of the Cyrus Cylinder (the original is in the British Museum).
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The monument acts as a grandiose gateway to the Iranian capital, and is surrounded by a large plaza (approx. 50,000 m²).

Built in 1971 in commemoration of the 2,500th anniversary of the Persian Empire, this “Gateway into Iran” was named the Shahyad Tower, meaning “Kings’ Memorial”, but was dubbed Azadi (Freedom) after 1979. It is 50 meters (164 ft) tall and completely clad in cut marble.

More info:
http://en.wikipedia.org/wiki/Azadi_Tower