N'guigmi is a city and Commune of fifteen thousand in the eastern most part of Niger, very near to Lake Chad - lying on its shore until the lake retreated.

N'guigmi is a military center for the region, a centre for the salt trade from Kaourar and is the last stop on the road to Chad. It marks the end of the paved section of the Nigerien Route Nationale 1, although the sections past Diffa are notorious for their poor condition. Three unpaved highways connect to N'guigmi from the north, providing the main road route between Chad and Niger, and another one of two land routes to the Kaourar Oasis town of Bilma.

The town lies at the mouth of the Dilia Bosso, an ancient river valley and seasonal wash that runs from the Termit Massif over 200 km to the northwest to what was the shore of Lake Chad as recently as the mid 20th century. The town was then a centre of Kanuri fishing communities. By the 2000s, even during the rainy season, the nearest access to water was at the village of Doro (a Beri-beri name for "Fishing port") 45 km southwest of N'guigmi. During the Sahel drought of the mid-1970s the shore was 85 km away from N'guigmi in Chad.