Getting to Oualata is the hardest part of the trip, and it's quite hard. The town sits near the Malian border in southeastern Mauritania, and the nearest real settlement is Néma, roughly 100 kilometres to the west.
From Néma, 4WD vehicles can reach Oualata in two to three hours in dry conditions, though there is no marked road for much of the journey — a local guide or driver who knows the desert is essential. Do not attempt this route in a standard vehicle. Fuel should be carried, as nothing is available between Néma and the town.
Néma is served by occasional flights from Nouakchott, and by a long bus or 4WD journey east across the country. The flight is the more reliable option in the rainy season, when the desert tracks become impassable. Allow several days of flexibility for the journey in either direction; this is not a place you can be in a hurry to leave.