My recollections of the 1960s are vague. As a child I was almost entirely focussed on my immediate environment. The 1970s were a different matter. Events in the Middle East and in Iran began to intrude on my childhood. New of conflicts in Palestine and in the wider region became part of my consciousness.
Many of us will be aware that Shah left Iran for exile in January 1979, as the last Persian monarch, leaving his duties to a regency council and Shapour Bakhtiar who was an opposition-based prime minister. Ayatollah Khomeini was invited back to Iran by the government, and returned to Tehran to be greeted by several million Iranians.
“Demonstrations against the Shah commenced in October 1977, developing into a campaign of civil resistance that included both secular and religious elements. The protests rapidly intensified in 1978 as a result of the burning of Rex Cinema which was seen as the main cause of the Revolution. Between August and December 1978, strikes and demonstrations paralyzed the country”  and led to the departure of the Shah at the beginning of 1979.
Wikipedia  says of the 1970s: “Several events in the 1970s set the stage for the 1979 revolution. The 1971 2,500-year celebration of the Persian Empire at Persepolis, organized by the government, was attacked for its extravagance. As the foreigners reveled on drink forbidden by Islam, Iranians were not only excluded from the festivities, some were starving.  Five years later the Shah angered pious Iranian Muslims by changing the first year of the Iranian solar calendar from the Islamic hijri to the ascension to the throne by Cyrus the Great. Iran jumped overnight from the Muslim year 1355 to the royalist year 2535.” [5: p444]
“The oil boom of the 1970s produced an alarming increase in inflation, waste and an accelerating gap between the rich and poor, the city and the country, [9: p94] along with the presence of tens of thousands of unpopular skilled foreign workers. Many Iranians were also angered by the fact that the Shah’s family was the foremost beneficiary of the income generated by oil, and the line between state earnings and family earnings blurred.” 
“By 1976, the Shah had accumulated upward of $1 billion from oil revenue; his family – including 63 princes and princesses had accumulated between $5 and $20 billion; and the family foundation controlled approximately $3 billion. [10: p285]. By mid-1977 economic austerity measures to fight inflation disproportionately affected the thousands of poor and unskilled male migrants to the cities working construction. Culturally and religiously conservative, [11: p163] many went on to form the core of the revolution’s demonstrators and “martyrs“.” [9: p226]
“All Iranians were required to join and pay dues to a new political party, the Ḥezb-e Rastakhiz party – all other parties were banned.[11: p174] That party’s attempt to fight inflation with populist “anti-profiteering” campaigns – fining and jailing merchants for high prices – angered and politicized merchants while fueling black markets.”  [9: p96]
Although, in 1977, the Shah responded to the “polite reminder” of the importance of political rights by the new American president, Jimmy Carter, by granting amnesty to some prisoners and allowing the Red Cross to visit prisons. Throughout 1977 liberal opposition formed organizations and issued open letters denouncing the government. [5: p501-503] “Against this background a first crucial manifestation of public expression of social discontent and political protest against the regime took place in October 1977, when the German-Iranian Cultural Association in Tehran hosted a series of literature reading sessions, organized by the newly revived Iranian Writers Association and the German Goethe-Institut. In these “Ten Nights” (Dah Shab), 57 of Iran’s most prominent poets and writers read their works to thousands of listeners. They demanded the end of censorship and claimed the freedom of expression.” 
“Also in 1977 the popular and influential modernist Islamist theorist Ali Shariati died under mysterious circumstances. This both angered his followers, who considered him a martyr at the hands of SAVAK (The Shah’s secret police), and removed a potential revolutionary rival to Khomeini. Finally, in October Khomeini’s son Mostafa died of an alleged heart attack, and his death was also blamed on SAVAK. A subsequent memorial service for Mostafa in Tehran put Khomeini back in the spotlight.” [11: p184-5][13: p182-3]
The Railways of Iran were to some great extent lost in the political turmoil. However, right at the end of the 1960s Iran Sate Railways sought additional diesel motive power from external suppliers. Delivery was taken of a number of power units in the very early 1970s. A further lot of locomotives was delivered in 1975. Wikipedia indicates that these locomotives were in three different lots: 
In 1970: 37 No. Hitachi HD10C Locomotives which had numbers within the range 601-638 in Iranian State Railways Class 40. They weighed 68 tons, were rated at 709 kW with a tractive effort of 122 kN and a top speed of 100 km/hr.  There are a few pictures of these locos in service in Iran on Flickr and http://www.farrail.com, including:
……………………….https://www.flickr.com/photos/alcoalbe/5380090479, ……………………….https://www.farrail.com/pages/touren-engl/Railways-in-Iran-2016.php, and ……………………….https://www.flickr.com/photos/alcoalbe/5382251132
In 1971: 92 No. EMD-GT26CW Locomotives numbered 501-569, 801-914, 975-984 in Iranian State Railways Class 60. They weighed 120 tons, were rated at 2205 kW with a dynamic brake power of 1500 kW. They provided a tractive effort of 235 kN and a top speed of 123 km/hr.  There are some pictures of these locos on Flickr, including:In 1975: 41 No. EMD-G22W Locomotives which were numbered 138-178 in Iranian State Railways Class 40. They were rated at 1103KW with a tractive effort of 116 kN and a top speed of 105 km/hr.  A number of pictures of these locomotives are on the http://www.railpictures.net website and on Flickr. These include:
Not in Iran, but in Brazil, this picture of an EMD-G22 Locomotive has a Creative Commons Licence, (c) Heron Soares. The Locomotive is an EMD-G22U of Rede Ferroviária Federal S.A. MACOSA No. 4392-6L working on the Teresa Cristina Railroad – Paraná, Brazil. The suffix ‘U’ indicates narrow- rather than standard-gauge (which would have the suffix ‘W’). 
During the 1970s, the railways Iran remained under the control of Iran State Railways. A number of schemes to extend the railways were undertaken during this time. Wikipedia talks of the following schemes:
The length from Tabriz to Bazargan (192 km) which was started in 1912 was not finally completed until 1971. Please see the notes below as this date and destination need to be verified. The more southerly of the lines referred to in the section below was not completed until 1977. 
The length from Qom (Qum) to Zarand (847km) which was started in 1939 was not finally completed until 1971.
The length of line between Isfahan and Zarrin Shahr (111km) was started in 1969 and finished in 1972.
The length from Zarand to Kerman (80km) was not started until 1975 and was finished in 1979.
Tabriz to Bazargan: We noted the size of Tabriz in the second articles in this series.  Bazargan is a city in Maku County, West Azerbaijan Province, Iran. It is the most important Iranian ground border for importing and exporting. from Turkey In the 2006 census, its population was 9,047, in 2,126 families.  The railway station in Tabriz in 21st century is shown on the two adjacent satellite images (Google Earth). North of the station is the Railway Maintenance Centre. North of Tabriz the railway line becomes single track. The Railway line can be followed on Google Earth to Sahlan, where a Station serves a special economic zone. Northwest of Sahlan the railway passes under the Marand-Tabriz Road and runs parallel to it for some distance, alternately on its Southwest and Northeast sides and passing through a number of stations on the way.
The railway divides to the West of Soufian. The more northerly route heads for Marand. Near Marand the highway begins to climb and the railway needs space in order to gain height. Two switchback curves provide room for the gradient to be kept manageable. These appear on the satellite image below.The railway then runs round the Eastern outskirts of the city of Marand to its railway station, sown on the adjacent satellite image. It then passes under the Marand-Hadishahr Road and parallel to the Marand-Jolfa Road. The line continues all the way to Jolfa and the border with Armenia and Azerbaijan.
The more southerly route heads Southwest on the south side of Souflan, running roughly parallel to Route 14, through Dizaj Khalil Station and Sharafkhane Station and on into Iran’s West Azerbaijan Province. It travels on through Salamas, Yazdekan and through dramatic mountains to Razi and Kapikoy, crossing the Ghotour Bridge on the way.The Ghotour Bridge (Google Earth (c) Behzad Monajjemi, 2019)
I have followed both the lines above on Google Earth and looked at various online resources and cannot identify the route of a line between Tabriz and Bazargan. I am not sure, therefore which of these two routes the Wikipedia article relates to. The relative locations of the cities concerned are shown on the Google Maps extract below.
The line through Kapikoy and into Turkey extend to Vana dn is often referred to as the Van-Sufian Railway 
“The oldest segment of the railway dates back to the early 20th century, during World War I, when a 53 km (33 mi) branch railway was built from Sufian to Sharafkhaneh ” 
Wikipedia explains that ,”the construction of a railway to Iran, via Van, was approved on 15th June 1937. The railway would continue east from Diyarbakır to Van and to the Iranian border at Kapıköy. [31: p123] Construction began shortly after and the railway reached Kurtalan in 1940. Due to the mountainous terrain between Kurtalan and Tatvan, the route was changed and its western starting [point] became Elazığ. From Elazığ the railway would be built to Tatvan, via Muş, reaching Tuğ in 1964. [31: p174] A train ferry was established as a temporary means of transport between Tuğ and Van, as a bypass of Lake Van was planned. [31: p175] In the 1960s, Turkey and Iran came to an agreement to construct a railway from Van to Sharafkhaneh. The Van-Razi segment opened in 1971, while the Razi-Sharafkhaneh segment opened in 1977.” 
Isfahan to Zarrin Shahr: A 111km length of line was constructed between 1969 and 1972. Isfahan is located 406 kilometres (252 miles) south of Tehran. It has a population of approximately 2.0 million, making it the third largest city in Iran after Tehran and Mashhad, but was once one of the largest cities in the world. 
“Isfahan flourished from 1050 to 1722, particularly in the 16th and 17th centuries under the Safavid dynasty when it became the capital of Persia for the second time in its history under Shah Abbas the Great. Even today the city retains much of its past glory. It is famous for its Perso–Islamic architecture, grand boulevards, covered bridges, palaces, tiled mosques, and minarets. Isfahan also has many historical buildings, monuments, paintings and artefacts. The fame of Isfahan led to the Persian pun and proverb “Esfahān nesf-e- jahān ast”: Isfahan is half (of) the world.” The Naghsh-e Jahan Square in Isfahan is one of the largest city squares in the world, (c) Arad Mojtahedi, used under a Creative Commons Licence. The modern, 21st century, Isfahan Station is some distance (15km) outside the city to the South (Google Earth).Isfahan Railway Station. Isfahan Railway Station is shown in the top right of this Google Maps extract. Trains to Zarrin Shahr left travelling East and then reversed to head Southwest. The topography dictated that the line had to loop around in order to allow trains to negotiate significant differences in height. The distance between the two cities by road (along Route 51) is only 47km. The railway is 11km in length!The route to Zarrin Shahr was a branch line which served an industrial complex on the North side of the city of Zarrin Shahr.
The station was to the Northeast of the city. It can just be seen at the top of the adjacent Google Maps excerpt.Zarrin Shahr is, as of the 2006 census, a city with a population of 55,984, in 15,154 families.  In the past 30 years people, from various parts of Iran have moved to Zarrin Shahr to work in the nearby steel mill  which is served by the railway and sited to the North of the city.
Earlier in this series of articles we provided a Satellite Image of Qom (Qum) Railway Station. . The adjacent Google Maps extract shows the station site. The line to the North of the station heads for Tehran. South of the station there is a junction to the Northwest of the Mosalla Metro Station. The line heading Southwest runs towards Arak and the South, and that turning to the Southeast heads for Yazd and Zarand. The line to Zarand was close to 850km long!
Yazd was encountered first around 500 km from Qum.Yazd Railway Station Building in the 21st century, (c) Hamid Khorshidi on Google Maps.Yazd Railway Station in the 21st century (Google Earth).A large mineral train travelling between Zarand and Yazd, captured in the 21st century on the satellite imagery from Google Earth.
Zarand is a city of more than 54,000 people in the early 21st century.  It is also home to the Zarand Iranian Steel Company (ZISCO).  ZISCO was established in 2008. 
Zarand to Kerman: The extension of the line from Qom to Zarand to the provincial capital city of Kerman was complete in 1979. The route was direct across relatively open plains. These appear to be either coal of iron ore sidings parallel to the main line between Zarand and Kerman. The strong black lines visible on the satellite image are long trains of open wagons in what appear to be exchange sidings (Google Earth).This satellite image shows the exchange sidings highlighted on the previous image alongside the main Zarand to Kerman line in the top left of the image. A branch line which serves the min complex in the centre of the image can be seen curving away from the main line and leading a complex of sidings to the Southwest side of the mining site (Google Earth) .Kerma Railway Station, taken on 13th June 2009 (c) Teekkari, used under a Creative Commons Licence. The station is to the Southwest of the city and a little distance beyond the outskirts of the city. Kerman Railway Station is to the Southwest of the city (Google Earth). It is shown in gradually increasing detail on these three satellite images.
At the 2006 census, Kerman’s population was 821,394, in 221,389 households, making it the 10th most populous city of Iran.
Wikipedia comments: “Kerman is … the most important city in the southeast of Iran. It is also one of the largest cities of Iran in terms of area. Kerman is famous for its long history and strong cultural heritage. The city is home to many historic mosques and Zoroastrian fire temples.
Railway development in Iran has continued apace from the 1980s through to the early 21 century. I hope to cover more about about these more recent developments in further posts.
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- Ervand Abrahamian; Mass Protests in the Islamic Revolution, 1977–79; in Adam Roberts and Timothy Garton Ash (eds.), Civil Resistance and Power Politics: The Experience of Non-violent Action from Gandhi to the Present; Oxford University Press, Oxford & New York, 2009, p162–78.
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