Four Moroccan cities, led by Marrakesh, ranked among the top 10 African cities for quality of life in a new survey published Tuesday.

Marrakesh, nicknamed the Ochre City for the walls surrounding its old Medina district, clinched the top ranking, with three other Moroccan cities -- Casablanca, Rabat and Fez -- in the top 10.

"They are cities that are not huge, where real work has been done to improve infrastructure, people's quality of life (and) housing in a stable political context," said Swiss urban sociologist Jerome Chenal, who directed the survey.

The study of 100 cities, which included all of the continent's capitals and its largest urban centers, was based on criteria including social and living conditions, infrastructure, governance and environment.

Johannesburg and Cape Town scored second and ninth, respectively, while Egypt also had two cities in the top 10, Alexandria and Cairo, in the first survey focusing on life in African cities for ordinary people.

"Until now, rankings for Africa were done for investors and expatriates," Chenal told Afrique Mediterranee Business, the Paris-based magazine that commissioned the study.

"We never asked how people lived, whether young or old, rich or poor," he told AFP.

The Mauritius capital Port Louis came fourth, while Tunis was sixth in the study  at the Federal Institute of Technology in Lausanne (EPFL).

EPFL says it will conduct the study each year in the hope of standardizing data on African cities.