With the downfall of the Qajar dynasty and rise of the Pahlavi between 1938 and 1958, came more developments in the social, economic and political affairs in iran.
Tehran also underwent major changes, most of which were novel and modern. Installations reflecting the new civilization rapidly developed in Tehran. This development was incompatible with the walls remaining from the time of Nasser ed-Din Shah.
The increase in population and the need for open spaces for development called for for the removal of the walls which had long functionally lost their limiting quality because houses and gardens were developed outside the walls.
The creation of new steerts with rectangular intersection similar to those in European cities, and also the creation of new educational centers and economic and social buildings. Brought new architecture to the city which was different from that of the old urban texture.
The population of Tehran between 1340 and 1357 AS (1961 to 1978 AD) increased from 2 million to 5 million. During this period in addition to the creation of satellite cities and urban developments around the city, the townships of Rey and Shemiran were incorporated into Tehran.
Immigration after the Islamic Revolution in 1978 and new development caused the creation of a territory called Tehran with a population more than 10 million.
Today, it covers an area spanning the foothills of the Alborz range on the north to Rey in the south.
Tehran, as a metropolis, is a city of sharp contrasts: a city which accommodates people from a variety of a different places with a variety of different cultural, social and economic backgrounds and yet it belongs to all of them.
All in all, Tehran is a city full of mystery, beaty and wonder, nestling in the shadow of the mighty Alborz mountain range which embraces it from the north.