World music rhythms through the day and deep into the night. Informal discussions about djinns at dawn. What makes the annual Fes World Sacred Music Festival unique is not just that it brings together more than 250 musicians from 30 different countries in one of the largest celebrations of spiritual music on the planet, but that it fosters dialogue between diverse peoples - Moroccan Arabs, Africans, Muslims from the Middle East, tourists from Europe and the United States, Asian visitors from countries like India and Japan.

This music extravaganza has wisely chosen the 1, 200-year-old Moroccan city of Fes as its home. Faded and yet imperial, the city's labyrinthine medina is considered the oldest medieval Islamic settlement on earth and has served up a simmering couscous of cultures and religions over centuries. Groups of Sufis gather in secretive nooks, even as the many mosques in the valley echo more formal calls to prayer.

The festival was founded in 1994 by Dr Faouzi Skali, a Sufi scholar, who said he was disturbed by the widening chasm between the West and the Muslim world after the 1991 Gulf War. While Sufi music forms the beating heart of the festival, performances include myriad spirituals - Vedic mantras, Tibetan meditations, Jewish and Christian liturgies, orthodox Ethiopian chants.

Woven into the festival programming this year was a distinctive Indian presence. The Divana ensemble consisting of Manghaniyars and Langas from Rajasthan was received warmly. Lamps flickered in a darkened room as these Sufi musicians provided the soundtrack to Franz Osten's luminous 1925 film Prem Sanyas - The Light of Asia, a silent, voluptuous delight evoking the early years of Buddha. Shot in Jaipur, it provided a compelling storyboard for the Divana's evocative music.

The second Indian group presented a different dimension - dhrupad, the oldest surviving form of Indian classical music inspired by Vedic mantras and hymns. The Gundecha brothers - Umakant and Ramakant - are considered masters of the form. Scarf-wearing Arab women watched as the brothers started with a long alap and then went on to evoke the mystical poet Kabir and Hindu gods like Shiva. For 32-year-old Moroccan Nezha Youseffi, this was her first experience of Indian classical music even though she had heard a lot of Bollywood beats before. Asked what it felt like to be listening to an invocation to Hindu gods, Youseffi pointed out that Morocco has always been open to different cultures and traditions. After the concert, Ramakant echoed Youseffi - he said that he would not have been able to sing with such abandon in, say, Abu Dhabi, where singers are required to provide a translation of their songs.

Indian-American Zeyba Rahman, the festival director for North America and Asia, is also a fan of Morocco's plurality. This year, she was particularly pleased by the strong presence of Indian artistes. Rahman now plans to bring the festival to Asia, beginning with a dozen touring musicians. That could make for an otherworldly exchange as Moroccan musicians bring a slice of Fes to India.

Besides Rajasthani sufi and dhrupad, the 10-day gathering was served up with a mesmerising mix of melodies - Andalusian music echoing the shared history of Muslims and Jews, Sephardic and Palestinian traditional songs, Pakistani qawwali, Christian gospel, Afghani rubab, and even rap from African-French slam poet Abd Al Malik. Not all the music fits the clipped definition of the term 'sacred' but the overarching sensibility is that of a higher purpose.

It all began at the Bab Makina, the grandest venue at the festival. Built in 1886 as a royal entrance to the medina, its massive arched gate is surrounded by crenellated ramparts. Every evening, the concerts here were heralded by twittering swallows preparing to roost.

The first musical tale was the universal love story of Laila and Majnu. Performed as an opera, 40 artistes of mixed ethnicity rendered the tale of absolute love, as Japanese drums and brass trumpets harmonised with the primordial sounds of ancient instruments like the duduk, ney and oud.

A few days later, Bab Makina was taken over by the popular Senagelese musician Youssou N'dour. Drawing an audience of more than 3, 000, N'dour and his group the Super Etoile of Dakar throbbed with energy.

A less known fact about N'dour is that he is a member of the Tijaniyya Sufi sect. His performance was dedicated to the founder of the Tijaniyya Brotherhood. N'dour takes part in the festival regularly and is rumoured to disappear for a few hours on the day of every performance - presumably to visit the shrine of his Sufi muse.

As artistes hurled across the stage in exuberant acrobatics, people danced in the aisles. "Youssou gave me so much energy, I had to give it back. I stood and danced and really felt it, " said Elly Ridez, a French New Yorker. "It's much more than music, it's beyond race or religion. He was singing about Prophet Muhammad, and I'm not Muslim, yet we're all linked at one level. "