Grand Erg Oriental follow the wind's direction. There are other types of dunes, as well as "complex" dunes. Saharan winds are also known to clear an area of sand altogether, leaving bare rock (hamada) or gravel (reg). The "Grand Erg Oriental" is accessible overland by an Algerian road, which goes south from Constantine. It passes through the Aurès mountains, then salt lakes by the city of Biskra. Next the road skirts the western edge of the erg. After about 500 km. in all, it reaches the ancient oasis of Ourgla [Wargla]. Since late antiquity Wargla was a stop for the Saharan trade, being
What Love Is Made Of it in "Little Red" (2014). Upon its release, "What Love Is Made Of" received generally favorable reviews from contemporary music journalists, who favored the composition and Katy's distinctive vocal performance. It peaked at number 21 on the UK Singles Chart, and entered three other charts, reaching the top 40. To promote the song, Katy performed it live at the BBC Radio 1Xtra Live special and at her headline set during the Wireless Festival. Emil Nava also filmed and directed a music video for the song which was deemed similar to film series "The Fast and the Furious". In April 2011,