ISTANBUL // When Olga, a young woman from Ukraine, arrived at the visitors' entrance of Istanbul's famous Blue Mosque this week, a surprise was waiting for her.
"Please wear this," a female mosque official told Olga, 28, who was dressed in a sleeveless shirt and shorts. She was handed a blue cotton robe that covered her whole body, with an attached piece of cloth to cover her hair.
Authorities in Istanbul began providing the robes, as well as headscarves and skirts, this week in an effort to preserve a semblance of serenity at the city's places of worship that are visited by millions of camera-wielding and sometimes scantily clad holidaymakers every year.
At the Blue Mosque's entrance for tourists, visitors were first asked to take off their shoes and put them into plastic bags provided for the purpose. As the tourists went on towards the door leading to the mosque's main prayer room, three officials watched to see who was inappropriately dressed.
A plastic mannequin in the walkway, dressed in a robe and a headscarf, served as a model of how visitors should dress.
Olga closed the zipper that ran down the length of her robe as she walked towards the door leading into the mosque with her friend Jelena, 29. Both women gave only their first names.
"You should respect religion," Olga said. "It's OK if those are the rules."
All mosques in Istanbul are closed to tourists during prayer times.
The Blue Mosque, known as Sultan Ahmet Camii in Turkish, after the Ottoman sultan Ahmet I who had it built from 1609 to 1616, gets its English name from the blue tiles in its interior. It draws four to five million tourists a year, according to the office of Istanbul's mufti.
The deputy mufti, Sabri Yilmaz, said the new robes represented a "more professional" way to make sure that tourists' attire was in line with religious rules.
"We have been giving out scarves to tourists in mosques for 30 years," Mr Yilmaz said this week. "But it has been a bit amateurish. This is more professional."
Mr Yilmaz said the robes were not a way to tell people what to wear.
"This is not about fashion, everybody can wear what they like," he said.
"If people from Africa or from Europe come to the mosque in traditional clothes that are acceptable [from a religious standpoint], then in they go. What matters to us are religious rules."
Signs around the Blue Mosque explain those rules to visitors: men should wear long trousers, but can wear short-sleeved shirts. Women should cover their hair and arms, as well as their legs from the knees up.
At the entrance, visitors have three choices, depending on the modesty of their dress. Apart from the full-body robes, which come in blue and green, there are turquoise headscarves and blue skirts with Velcro fastenings.
While headscarves were for women, the robes and skirts are for visitors of both sexes.
"I feel very strange," said Alan Sarsa, a tourist from Sweden, as he looked down at the blue skirt covering his shorts and legs.
Mr Yilmaz said the reusable garments represented an effort to strike a balance between the rights of worshippers and the interests of tourism at the city's mosques.
"They are houses of worship as well as interesting places for visitors."
The garments were designed by a team made up by representatives of Istanbul's mufti and atour guide association, to make sure they complied with religious rules and were easy to use for visitors. Tourists return the garments as they leave the mosques. The use of the garments is free, with Istanbul's municipality paying for the project.
Murat, a helper at the Blue Mosque, said summer months posed a special challenge for him and his colleagues.
"When it gets hot, people come with short clothes. Some almost come naked," he said.
But other officials said many tourists knew about basic rules of attire for mosques and came with their own headscarves.
"Today's travel guides tell people what to wear in a mosque," said Yakup Sari, a representative of the Sultan Ahmet Mosque Protection and Improvement Foundation, which oversees cleaning and technical services at the mosque.
Mr Sari said there was still no verdict on whether robes, headscarves and skirts had fashion appeal.
"I don't know whether they are chic, that's for the ladies to decide," he said.
Only a few visitors showed displeasure with the new rules.
"I have come here so often with these shorts and it's never been a problem," a foreign tour guide complained as an official asked him to put on a blue skirt.
A woman from Italy, who had brought her own headscarf, was irritated when she was asked to put on a skirt to cover her tight leggings.
"I thought I was modest already," she said.