Mamou is a city and sub-prefecture in a valley of the Fouta Djallon area of Guinea. The population is 376,269. It grew around the railway line fro…Mamou is a city and sub-prefecture in a valley of the Fouta Djallon area of Guinea. The population is 376,269. It grew around the railway line from Conakry to Kankan and soon became the local administrative headquarters. Its main industry used to be until the 1990s decade meat processing, while it also acts as an important transport hub. All vehicles going to the Fouta Jallon, the forest region or Haute Guinée have to travel through Mamou.