Guerou is a city and department in south-central Mauritania.Guerou is the largest province after province Kiffa capital of Assaba Region. It is located at around 16°49′N 11°50′W / 16.817°N 11.833°W / 16.817; -11.833Coordinates: 16°49′N 11°50′W / 16.817°N 11.833°W / 16.817; -11.833.