What remains of the old fortified town of Tindouf sits at the centre of the modern grid, mostly buried under concrete and concrete-block construction from the French and Algerian-state eras. A few stretches of mud-brick wall, a couple of restored gateways, and the lines of one or two old caravanserai courtyards survive. The pace of visiting is slow — you walk between the modern buildings, ask permission to enter the surviving compounds, and read the place as much from absence as from presence.
The old market and the small museum of regional history occupy a partially restored complex on the western side of the centre and are the most rewarding stop. Open hours are erratic — when the curator is in town. Ask at your hotel; the place is small enough that someone will know where the keyholder is.