Just west of Siwa, the cultivated oasis simply stops and the Great Sand Sea begins — an endless landscape of soft sand mountains running all the way to the Libyan border. Almost every visitor takes a half-day or full-day 4WD safari out into the dunes, usually arranged through their guesthouse for around $30-50 per person.
The trip is part desert tour, part adrenaline ride: drivers crest the steep faces of dunes and plunge down the far side, stop at hot springs in the middle of nowhere, and offer sandboarding on the bigger slopes. Sunset trips end with mint tea on top of a dune, watching the sand turn pink and then violet.