Fortanga (Ingush: Форта/Фарта, romanized: Forta/Farta; Chechen: Марта, romanized: Marta) historically sometimes referred as Balsu, is a river in North Caucasus that flows in Ingushetia and Chechnya. The length of the river is 69 km, the basin area is 526 km².^[1]

The river originates near the border of Chechnya and Ingushetia on the northern slope of the Tsoreylam (Khaylam) ridge.^[2] In the upper course it is called Martanka.^[3] Flows to the northeast. The mouth of the river is located near the village of Shaami-Yurt, 7.5 km along the right bank of the Assa River. The length of the river is 69 km.^[1]

Settlements standing in the Fortanga river basin: Khay, Khayara, Tsechakhki, Singalhi, Gand-Alie, Phumatiye, Katargashtiye, Mulkaniye, Muzhak, Mashtie, Mazanty, Dekashari, Gozuni, Meredzhi, Dakih, Khaykhara, Gerety, Dalg-Bukh, Dak-Bukh, Egichozh, Egiboss, Dattykh, Belkhara, Gandalbos, Arshty, Izdig, Futtunchie, Akati , Bereshki, Samiogochie, Mergyiste, Bamut, Achkhoy-Martan, Shaami-Yurt.

• Сулейманов, А. С. (1978). Шайхиев, А. Х. (ed.). Топонимия Чечено-Ингушетии. Часть 2. Горная Ингушетия (юго-запад) и Чечня (центр и юго-восток) [Toponymy of Checheno-Ingushetia. Part 2. Mountainous Ingushetia (southwest) and Chechnya (center and southeast)] (in Russian). Грозный: Чечено-Ингушское Книжное Издательство. pp. 1–233.
• Барахоева, Н. М.; Кодзоев, Н. Д.; Хайров, Б. А. (2016). Ингушско-русский словарь терминов [Ingush-Russian dictionary of terms] (in Ingush and Russian) (2 ed.). Нальчик: ООО «Тетраграф». pp. 1–288.
• Кодзоев, Н. Д. (2021). Хайрова, Р. Р. (ed.). Русско-ингушский словарь [Russian-Ingush dictionary] (in Ingush and Russian). Ростов-на-Дону. pp. 1–656. ISBN 978-5-906785-55-8.{{cite book}}: CS1 maint: location missing publisher (link)
• Мальсагов, З. К. (1963). Оздоева, Ф. (ed.). Грамматика ингушского языка [Grammar of the Ingush language] (in Ingush and Russian). Vol. 5 (2nd ed.). Грозный: Чечено-Ингушское Книжное Издательство. pp. 1–164.