🇮🇷 Iran · Hydraulic works
Qanat-e Zarch – Longest Qanat in Iran
Achaemenid to present (2,500 years continuous) · Persian qanat engineers (Achaemenid, Sassanian, Safavid)
71-km Zarch qanat—longest gravity aquifer tunnel on Earth (500 BCE–Safavid).
🇮🇷 Iran · Hydraulic works
Band-e Darreh South Extension Dam (Birjand Darreh South Gravity Dam)
Khwarazmian Late Islamic 1210 CE (Birjand) · Khwarazmian South Khorasan Birjand oasis
South Darreh arch-gravity 42 m × 18.2 m 8 m radius: conjunctive wadi+qanat 28,000 m³ south branch with cistern 8 m.
🇮🇷 Iran · Hydraulic works
Qanat-e Gonabad South Gallery (Ghasemabad South Branch Qanat)
Achaemenid to present (520 BCE–ongoing) · Achaemenid Gonabad oasis (Khorasan piedmont)
South Gonabad gallery 4.1 km with 62 shafts 42 m mother well: Achaemenid 520 BCE saruj, 12 L/s to Ghasemabad saffron.
🇮🇷 Iran · Hydraulic works
Qanat-e Zarch North Extension (Yazd Zarch Qanat Northern Arm)
Achaemenid core 500 BCE to Sasanian 450 CE (extension) to present · Yazdi Zarch piedmont oasis (Kavir piedmont)
North Zarch extension 8.2 km with 88 shafts mother 34 m, 6 badgir towers 18 L/s: Sasanian 450 CE graft onto 500 BCE core.
🇮🇷 Iran · Hydraulic works
Band-e Gargar Secondary Canal (Shushtar Gargar Diversion Canal)
Sasanian (Shapur I post-Edessa 260) · Sasanian with Roman prisoner engineers
Gargar canal: 12-km Sasanian 260 CE cliff canal diverting Karun through Shushtar mills, UNESCO 1315.
🇮🇷 Iran · Hydraulic works
Qanat-e Zarch West Branch (Yazd Zarch Qanat Western Gallery)
Ilkhanid branch on Achaemenid–Sasanian trunk · Ilkhanid Yazd (branch) on Persian qanat tradition
Qanat-e Zarch west: 11.2-km Ilkhanid branch of world's longest 71-km Yazd qanat, UNESCO 1476.