London, England (CNN) -- For thousands of years men and women across the Middle East have retreated to their local hammams to sweat, get scrubbed and socialize with friends.
Public bathing dates back to the Greeks and the Romans. And though the tradition faded in much of the Western world, hammams remained popular in the Middle East, flourishing under the Ottomans --hence their English name "Turkish baths."
"The tradition of bathing held on because of Islamic praying," explained Magda Sibley, a researcher at the University of Liverpool School of Archaeology, referring to the Muslim decree that worshipers wash before prayers.
The first Islamic hammams were annexed to mosques to facilitate these ablutions. They soon became "very key urban facilities" said Sibley, promoting health and hygiene and providing a social meeting space, particularly for women.
"Depending on their importance to the social fabric, [hammams] developed near mosques, sometimes near souks, and also in the center of residential neighborhoods," Sibley told CNN.
Hammams vary widely in function and form, but the majority are strictly segregated between sexes and have three connecting rooms -- one hot, one warm and one cold. Typically hot is for steaming, warm for scrubbing, and cooler rooms are for lounging and relaxing. Public versions exist far and wide, from North Africa to Asia Minor, and from Spain to Eastern Europe.
In some majority-Muslim countries today such as Turkey, Morocco, Yemen and Syria, the tradition of going to hammams remains popular, but the ritual has broadly declined in the region.
According to French photojournalist Pascal Meunier, who has extensively documented hammams, the rise of more conservative strands of Islam in the 20th century made hammams less popular because they were often seen as subversive.
Meunier says that religious conservatives feared dissidents could use bath houses to organize opposition, that hammams were providing cover for homosexuality or that they were permitting women to behave loosely, letting them congregate without men and spend the day bathing freely with their children.
Where hammams still operate, Meunier describes an intimate portrait of social life.
"[Hammams] invite you to nap and to converse, sometimes up until the crack of dawn. [They are] private circles where ideas and secrets are shared, where weddings and business is decided underneath humid archways," he told Leica's LFI magazine.
"Women will spend all day in the hammam, men all night," he told CNN.
Meunier has spent years traveling through the Muslim world from Mauritania to Iran and has produced multiple books on hammams, including "Hammams: The Last Bathhouses" and "The Last Hammams of Cairo."
Today, most of these beautiful buildings have fallen into disarray. "The historic ones have never been fully protected, many have disappeared. In places like Cairo and Damascus, many have been demolished," said Sibley who has spent the past 10 years surveying historic hammams."The decline is amazing."