From southwest to northeast this area extends from coastal plains to high mountains, and then partly back down to dry plateaus. This pattern is repeated from south to north in Sistan-e Baluchestan Province.
The coastal plains are along the Persian Gulf(5) and the Gulf of Oman. Behind them rises the Zagros Mountains, which rise to over 4000 meters in numerous peaks. Beyond them is the Cenral Iranian Plateau. This includes the Great Salt Desert(6) and the Great Sand Desert(7). The plateau is bounded on Iran's northeast by the Kopet Dag mountains which rise to less than 3000 meters. In Sistan-e Baluchestan Province the plateaus rise above 4000 meters in the center, then fall below 500 meters in the province's northeast.
The majority of the 21 million people here speak dialects of Persian (Farsi or Parsi) but beyond that it is difficult to say. Minority language estimates vary by as much as two magnitudes.(8) Perhaps more than eight in ten speak Persian. Even so, the dialect variation is so great that, were there national boundaries between the dialects, and were there not a unifying literary language, the dialects would be classed as distinct languages.
The other two substantial languages are Luri and, arguably, Qashqay, a form of Azeri. Luri's dialects are often considered separate languages; together they make up between one int tweny and one in ten speakers. Qashqay nomads might be similarly numerous.
There are three cities with a million or more people, all of them former capitals of Persia: Esfahan, Mashhad and Shiraz.
Early mainstream linguistic developments
Common early religious developments
Southwestern Iran
Esfahan, Yazd, Kerman and Sistan-e Baluchestan Provinces
Khorasan
(1) Formerly Persia.
(2) '-e' is sometimes transliterated from Persian as 'va'.
(3) Also transliterated from Persian as Kohkiluyeh.
(4) 'Boyer' and 'ahmad' are sometimes spelled (in transliteration from Persian) as two words.
(5) Also called the Arabian Gulf.
(6) Dasht-e Kavir in transliterated Persian.
(7) Dasht-e Lut in transliterated Persian.
(8) The Qaushqay for example. Andrew Dalby estimates 100,000 in his Dictionary of Languages, while Ethnologue.com (5/2005) puts their numbers at 1.5 million.