الربع الخالي
The vast desert wasteland of southern Saudi Arabia known as the Empty Quarter, or "Rub' al Khali" in Arabic, is one of the most desolate places on Earth. In 1932, Harry St John "Jack" Philby was hunting for a city named Ubar, that the Quran describes being destroyed by God for defying the Prophet Hud. Philby transliterated the name of the city as Wabar.