The foundations of this historic riad are more than 400 years old, and it was once owned by powerful qaid (local chief) U-Bihi. Here, though, it's not the building but the traditional Islamic garden that is so special. Fed by a restored original khettara (underground irrigation system), the gardens are set up as a living museum to demonstrate the ancient waterworks. There's a good cafe on its ramparts and a tower with views across the medina (not worth the extra fee).

　　Khettara were first introduced to Marrakesh by the Almoravids in the 11th century to distribute water to the mosques, hammams and fountains of the growing metropolis. They are unique to Morocco, and the irrigation system at Le Jardin Secret was only discovered when workers started digging out the riad to restore it. The complex is divided into two parts, one planted as an exotic garden, the other as a traditional Islamic garden with fig, date, pomegranate and olive groves.

　　The bare riad chambers include excellent exhibits (in English, French and Arabic) on the riad's history, the importance of water in Islamic society and the role of gardens in Marrakesh culture. High-tech screens use CGI to expertly show the flow of water around the site, and there's also a fascinating documentary on the restoration process.