On the 3rd day of Luca and Melua's desert adventure, they finally reach the massive expanse of dunes that stretch out as far as the eye can see. As they drive up and down the enormous dunes, all they can see is a vast sea of sand - it's a long day, and their car gets stuck many times. But even when it seems like there is nothing more but sand to see, they still manage to discover some old fossilised dunes dating back thousands of years.