The Ténéré is 500 km north of Agadez and about 300 km north of the Aïr Mountains. It has incredibly beautiful sand dune areas, and anyone disappointed by their first desert experiences should absolutely come here — this is the real thing.
This is genuinely remote territory, so plan on at least a week starting from Agadez. Travel in a convoy of cars and hire at least one guide. The road to Bilma — not always a road in the western sense of the word — crosses the Ténéré from west to east and offers the best opportunities to explore this stunning region.