In the village of Kadabas, thousands of Sudanese people gather to worship at an enormous festival to celebrate their saints. Sufism is seen as a mystical branch of Islam. Its followers pursue a personal, inner path towards God through absolute absorption in worship. They aim to achieve this through music, dance and spinning in circles, and sometimes smoking marijuana, which can induce enough fervour to enter a heavenly trance. The festival was one of the most extraordinary gatherings I have ever seen. Food was given freely by volunteers and subsidized by donations from wealthy pilgrims. Dervish elders performed incredible ritual dances with swords, and at night the entire desert glowed a luminescent green, while music blasted out from singers and speakers alike. It lasted until dawn.