Shiler is a valley-like region in Iraqi Kurdistan, bordering the Marivan frontier district of Iran’ s Kurdistan Province. It witnessed the military confrontations throughout the eight years of the Iran-Iraq War.

The area takes its name from a river called Shiler and is known as the “ Shiler Mouth”. The most significant border section of Marivan in Kurdistan Province — situated between Baneh and Marivan — is Shiler Valley. This fifty-kilometer-long strip forms an indentation of Iraqi territory extending into Iranian soil.⁠[1]

The Shiler Mouth area borders Iraq’ s Sulaymaniyah Governorate, one of the Kurdish-populated regions of Iraq. The terrain is a mix of plains and elevated ground. Most of the heights are covered with oak forests, with the trees growing taller and wider toward the summits, limiting visibility.⁠[2]

The heights of Takht Odlan, Katersh, Neheni, and Kalakum lie in the northern part of the valley, while Bardeh-Rash, Kharankedar, Espi-Shireh, and Chalpan are in the south. At the tip of the indentation sits Mount Shiler. The area is mountainous and blanketed with dense oak forests.⁠[3]

Among the region’ s other heights is Zeleh, which overlooks the Iraqi city of Panjwin.⁠[4]

The geographical position and distinctive shape of Shiler Valley provided a favorable route for anti-revolutionary groups to infiltrate from Iraqi territory deep into Iran’ s Kurdistan Province. The Iraqis had their greatest access to Iran’ s interior through this area, since Marivan, its surrounding villages, and border routes were within range of most of the Shiler heights — a situation that made controlling the region’ s borders considerably more difficult.

In May 1981, after the Marivan Islamic Revolutionary Guard Corps (IRGC) under Ahmad Motavasselian cleared the Marivan– Saqqez Road, anti-revolutionary groups could no longer easily operate through the Shiler area.⁠[5] The 130-kilometer Saqqez– Marivan Road passes close to the Shiler promontory and Iraqi territory.⁠[6]

The first major Iranian operation in the northwest was Operation Valfajr 4. It was carried out in Shiler area by the Hamzeh Seyyed al-Shuhada Command Headquarters under joint IRGC and Army command at midnight on October 19, 1983, with the codeword “ Ya Allah, Ya Allah, Ya Allah”. The operation was conducted between Baneh and Marivan counties with the following objectives: seizing Shiler Valley and its protrusion into Iraqi territory; connecting the Sooren Heights to Soorkooh; shortening the defensive line of Iranian forces; removing Marivan and surrounding villages from enemy observation and fire range; and, if possible, capturing the Iraqi city of Panjwin along with Garmak Garrison and the villages nearby. Connecting the Soorkooh Heights southwest of Baneh in the north to the Sooren Heights west of Marivan in the south would have transformed the Shiler Valley border line from an indentation into a solid defensive line.⁠[7]

Additional goals included creating favorable conditions for political gains through the capture of the Shiler area, removing Marivan and its surroundings from Iraqi artillery fire, and cutting one of the main communication routes between anti-revolutionary groups and Iraq — a move that would have significantly decreased anti-revolutionary activities.⁠[8]

On October 25, 1983, Hojatoleslam Hashemi Rafsanjani, spokesman of the Supreme Defense Council, noted that Iraq had been using Shiler to destabilize Kurdistan, and described the first phase results and gaining control over the Shiler area as significant.⁠[9]

In the second phase of the operation, a number of Shiler border points were captured, including the Khaloozeh 2 Heights, Kaloo, Haft Tavana, the heights around the Iraqi city of Panjwin, the eastern ridge of the Zeleh Heights, the 1672 Heights east of the Sang-e Maadan on the Marivan axis, and the Shakh Naleshkineh Heights on the Baneh axis. Operation Valfajr 4 resulted in the full liberation of this area and made movement between Marivan and Baneh through the valley possible.⁠[10]

Not all objectives were achieved in the two phases, and the operation extended into a third phase.⁠[11]

To fully capture the Zeleh and Kani-Manga heights and establish a reliable defensive line, the third phase was carried out on November 3, 1983. The strategic heights of Sheikh Gazneshin and Shakh Tajer in Kani-Manga fell to Iranian forces, who then gained a commanding view over the Iraqi cities of Panjwin and Seyyed Sadeq.⁠[12]

In 1984, the Shuhada Special Brigade of the IRGC under the command of Martyr Mahmoud Kaveh advanced from Marivan and cleared the main anti-revolutionary bases in Shiler Valley.⁠[13] Consequently, a 300-kilometer area of Iranian territory and 700 kilometers of Iraqi territory — including the region’ s key heights, particularly Shiler Valley — was fully liberated, blocking the routes used by anti-revolutionary groups to move between Iraq and Iran. During the operation, 20 Iraqi infantry battalions, 11 commando units, 6 armored and artillery battalions, 65 tanks and armored personnel carriers (APC), 32 artillery pieces, 180 vehicles, and large quantities of light and heavy weapons were destroyed. Also, 12 aircraft and 5 helicopters were shot down. In addition, 8 tanks and APCs, 10 loaders and bulldozers, around 200 vehicles of various types, 20 106 mm recoilless rifles, 20 SAM-7 missiles, and large amounts of communications equipment, along with a number of small ammunition depots, were captured by the Iranians. During the operations, approximately 500 Iraqis were killed, 180 were wounded, and 905 were taken prisoner. 250 Iranian fighters who had been held captive by the Democratic Party and anti-revolutionary forces were also freed. Ali Rezaian, commander of the Hamzeh Seyyed al-Shuhada Tactical Headquarters, was martyred during the operation.⁠[14]

After Iran signaled its readiness to accept UN Resolution 598 on July 18, 1988, the areas under Iranian control were evacuated, and Iranian forces withdrew to the international borders.⁠[15]