The Erg of Bilma is a Dune Sea (Erg) in the Ténéré desert region of the south central Sahara. The Erg of Bilma stretches from Fachi, east of the Aïr Mountains in north central Niger, east past the town of Bilma, on to the Chadian border. It surrounds on three sides the oasis of Bilma, southernmost of a north south string of oasies of the Kaouar rise.

The ancient Bornu Empire to Fezzan caravan routes had to cross the dunes of the erg south of Bilma as the last major obstacle before reaching the sahel. While that traffic largely ceased after 1820, trade though the erg of Bilma continues from the Lake Chad region and the Termit Massif on a small scale.

Media related to Erg of Bilma at Wikimedia Commons

Coordinates: 18°11′42″N 14°00′00″E / 18.195°N 14°E / 18.195; 14

Bilma is an oasis town in north east Niger with a population of around 2,500 people. It lies protected from the desert dunes under the Kaouar Cliffs and is the largest town along the Kaouar escarpment. It is known for its gardens, for salt and natron production through evaporation ponds,date cultivation, and as the destination of one of the last Saharan caravan routes (the Azalai, from Agadez). On June 23, 2010 in Bilma was recorded the highest temperature ever in Niger with 48.2 °C (118.8 °F).

Its population is mostly Kanuri, with smaller Toubou, Tuareg, and Hausa populations, the last being a reminder of Bilma's role as a key stop in the Trans Saharan trade.

Bilma is the administrative seat of the Bilma Department, covering some 260,000 square miles (670,000 km²) of north eastern Niger. While it continues to produce salt in large natron salt pans, and this salt is still sold for livestock use throughout west Africa, tourism (based out of Agadez and the Aïr Mountains some 350 miles (560 km) to the east) is of growing importance.