The Uncertain Length Of The Iran-Afghanistan Border: A Geopolitical Enigma

The border between Iran and Afghanistan is approximately 921km (572 miles) long. It runs from the tripoint with Turkmenistan in the north to the tripoint with Pakistan in the south. The border traverses an arid, inhospitable region with few inhabitants, except in the Zabol-Zaranj area where the main border crossing is located. The border has been the site of clashes between the two countries, most recently in May 2023, when Iranian border guards and members of the Armed Forces of the Islamic Emirate of Afghanistan clashed.

The border is 921km long and runs from Turkmenistan in the north to Pakistan in the south

The border between Iran and Afghanistan is 921km long and stretches from Turkmenistan in the north to Pakistan in the south. The border traverses an arid, inhospitable region with few inhabitants, except in the Zabol-Zaranj area where the main border crossing is located.

Beginning at the tripoint with Turkmenistan in the Harirud River, the border proceeds overland just east of the Iranian town of Taybad. It then follows a series of short straight lines, passing through the Daryache-ye Namakzar and Daqq-e Patergan salt lakes. Two 'beaks' of Iranian territory protrude into Afghanistan along this section. The middle section, known as the 'Turkish section', consists of a series of straight lines through a plain with mountains to the south, ending at Kuh Siah mountain. Here, the border veers sharply east, cutting through Hamun Lake before turning south and following the Juy-e Siksar River down to its confluence with the Helmand River. From this point, the border is formed of a long straight line segment going southwest to the tripoint with Pakistan at Kuh-i-Malik Salih mountain.

The process of defining the border between Iran and Afghanistan was lengthy and complex. It was carried out in three stages by neutral arbitration commissions, firstly British and then Turkish. The southern section of the border, in Sistan, was the first to be addressed due to its strategic importance. In 1872, a British arbitration commission proposed a boundary that divided Sistan into "Sistan proper" on the Iranian side and "outer" Sistan on the Afghan side, with the Helmand River as the dividing line. This award was in favour of Iran and was only reluctantly accepted by Afghanistan in 1873, following the payment of an indemnity.

The central and northern sections of the border were addressed later, with the Turkish section being the last to be drawn between October 1934 and May 1935. The entire process of fixing the borders of Afghanistan was completed in 1935.

The border between Iran and Afghanistan has been the site of occasional clashes and tensions, particularly over water rights and the sharing of the Helmand River. Disputes over water allocation have a long history, dating back to the 1870s. In recent years, with the Taliban back in power in Afghanistan, tensions have escalated and violent clashes have erupted along the border.

The border traverses an arid, inhospitable region with few inhabitants

The border between Iran and Afghanistan is a 921-kilometre-long boundary that runs from the tripoint with Turkmenistan in the north to the tripoint with Pakistan in the south. The border traverses an arid, inhospitable region with few inhabitants. The region is characterised by its aridity and lack of hospitality, making it challenging for human habitation.

The border begins at the tripoint with Turkmenistan in the Harirud River and proceeds overland just east of the Iranian town of Taybad. It then follows a series of short straight lines, passing through the Daryache-ye Namakzar and Daqq-e Patergan salt lakes. This section includes two "beaks" of Iranian territory that protrude into Afghanistan. The middle portion, known as the "Turkish section," consists of straight lines through a plain with mountains to the south, ending at Kuh Siah Mountain. Here, the border veers sharply eastward, cutting through Hamun Lake before turning south and following the Juy-e Siksar River down to its confluence with the Helmand River.

The area surrounding the border is sparsely populated, with the exception of the Zabol-Zaranj region, where the main border crossing is located. This area serves as an important commercial crossing between the two countries. The border then continues southwest towards the tripoint with Pakistan at Kuh-i-Malik Salih Mountain.

The arid and inhospitable nature of the region can be attributed to various factors, including the lack of water resources and challenging terrain. The allocation of water from the Helmand River, which flows from Afghanistan towards eastern Iran, has been a longstanding dispute between the two countries, dating back to the 1870s. The construction of dams and the impact of climate change have further intensified this dispute in recent years.

The border region is also known for its security concerns, with Iranian officials blaming the Taliban for disregarding international laws and border protocols since their takeover of Afghanistan in 2021. Clashes between Iranian and Afghan guards have occurred on multiple occasions, although they have rarely led to casualties. Both countries have issued statements aimed at de-escalating tensions and resolving issues through diplomatic channels.

The border has six official crossing points

The border between Iran and Afghanistan is approximately 921km (572 miles) long. The border traverses a generally arid, inhospitable region with few inhabitants, except in the Zabol-Zaranj area where the main border crossing is located.

There are three major border crossings: Islam Qala in the northern area, Abu Nasr Farahi in the middle area, and the Zaranj border crossing in the southern Baluchistan area. The Zaranj border crossing is the major crossing point. Most goods and products enter Afghanistan through the Zaranj crossing, and this is also where most Afghan refugees attempt to enter Iran.

There are a further three border crossings between the two countries, which are open to foreigners but are considered less safe due to Taliban activity in the surrounding areas. These are:

• Milak-Zaranj: This is a multilateral border crossing, with direct flights from Zaranj to Kabul.
• Mahirood-Abu Nasr Farahi: This crossing connects Farah Province in Afghanistan to South Khorasan in Iran. The road on the Afghan side is allegedly controlled by the Taliban.
• Imam Nazar-Aaqina: A remote border crossing near Andkhoy that sees little traffic. The road is a dirt track that requires a 4WD vehicle and good preparation. There are no settlements on either side of the border.

The Helmand River flows across the border, and disputes over water rights have occurred since the 1870s

The Helmand River, flowing from the Hindu Kush mountains in Afghanistan, has been a source of contention between Iran and Afghanistan since the 1870s. The river flows through both countries, providing water for agriculture, fishing, and human consumption for millions of people.

In the 1870s, a British officer drew the Iran-Afghan border along the main branch of the Helmand River. This led to disputes over water rights, which have continued to the present day. In 1939, serious discussions between the Iranian government of Reza Shah Pahlavi and the Afghan government of Mohammad Zahir Shah resulted in a treaty over water allocation, which the Afghans never ratified.

The dispute intensified in the 1950s when Afghanistan built two dams on the Helmand River—the Kajaki and the Grishk—which restricted the water flow into Iran. Renegotiations continued until 1973, when the Iranian and Afghan prime ministers signed a treaty on sharing water resources. However, the accord was neither ratified nor implemented.

Since then, both countries have faced periodic droughts, and sequential Afghan governments have built, repaired, or upgraded dams on the Helmand River, further exacerbating the dispute. The Kamal Khan Dam, which is situated on the border with Iran, was inaugurated in March 2021 and has been a particular source of contention.

In recent years, there have been clashes between Iranian and Afghan border guards, with each side accusing the other of initiating the violence. These clashes have resulted in casualties on both sides and have raised fears of a larger conflict. Despite attempts to de-escalate the situation, Iran and Afghanistan continue to disagree over water rights, and the issue remains unresolved.

The border has been the site of clashes between the two countries, most recently in May 2023

The border between Iran and Afghanistan stretches for 921km (572 miles) and has been the site of several clashes between the two countries. The most recent of these occurred on 27 May 2023, when armed forces of the Islamic Emirate of Afghanistan clashed with Iranian border guards. The conflict arose from long-standing disputes over water rights to the Helmand River, which flows from Afghanistan into eastern Iran.

The dispute over the Helmand River dates back to the 1870s, when a British officer drew the Iran-Afghan border along the river's main branch. In 1939, the kings of Iran and Afghanistan signed an accord to share water rights, but the agreement was never ratified. In 1973, the prime ministers of both nations signed a treaty, which stipulated that Iran should receive an annual share of 820 million cubic meters of water from the river.

In recent decades, the issue has intensified due to war, displacement, dam construction, poor water management, and climate change. In May 2023, Iranian President Ebrahim Raisi warned the Taliban rulers of Afghanistan against violating Iran's water rights under the 1973 treaty. This prompted a response from the Taliban, who denied the accusation and called for dialogue to resolve the issue.

On 27 May 2023, clashes broke out between Iranian border guards and Taliban forces at the border between the Afghan province of Nimroz and Iran's Sistan and Baluchestan province. The conflict resulted in the deaths of two Iranian border guards and one Taliban soldier, with several others injured. Both sides accused each other of initiating the shooting but eventually issued statements aimed at de-escalating the situation. The Iranian authorities closed the Milak-Zaranj border post, a major commercial crossing, until further notice.

Following the clashes, Iranian and Afghan officials established contact to discuss the incident and prevent future occurrences. Iranian officials expressed their commitment to dialogue and cooperation, and the situation at the border crossing was soon resolved. Afghan officials also called for diplomacy and emphasised their desire for good relations with their neighbours.

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