For 35 years it has been illegal for women to appear in public without wearing a hijab in Iran - but hundreds have posted pictures of themselves without the headscarf on Facebook with the hashtag #MyStealthyFreedom.
The page is titled 'Stealthy Freedoms of Iranian Women' and was set up just 10 days ago but it has since been 'liked' by more than 148,000 likes by men and women.
Hundreds of women - whose real names have been kept a secret - are pictured in parks, beaches and roads, some alone and others with friends or partners - but all have their hair uncovered.
Wearing the hijab in public has been compulsory in Iran since the Islamic Revolution in 1979 and punishment can range from a fine to imprisonment.
The page was set up by journalist Masih Alinejad who left Iran in 2009 and now lives in the UK.
She first posted images of herself with the hijab to her own Facebook page but after it was liked thousands of times she decided to set up a dedicated page.
She told Yahoo News UK: 'I received a flood of comments from my female Iranian fans on a picture of myself joyously down the street in London.
'Women wrote to me saying they were envious of my freedom to not wear the veil. They said that sometimes, in stolen moments of liberation, they too, shed their scarves.'
Since setting up the page she receives as many as 50 images a day, 'from ordinary women who were not activists or dissidents.'
One woman, who posted a picture of herself while holding her hijab behind her, captioned the image: 'No words to say. Just that freedom is wonderfully enjoyable; even a brief moment of it.'
Another, who poses on a beach wearing a long-sleeved t-shirt, writes: 'I just want to have the right to CHOOSE! Maybe I would have even chosen to wear a scarf if I'd had options to choose from. But it hurts me so much when others make decisions for ME instead of myself.'
One poignant picture shows three generations of women with the caption: 'Hoping for the day this new generation can achive their simplest right before their hair turns gray'.
Facebook, and social media is general, 'has turned into a mirror for Iranian women who have no access to official media', Masih said.
'All media in Iran is controlled and censored. [The] slightest step outside the norms can mean that you are banned.'
The overwhelming response has 'humbling', but the trend is not without its dissenters.
Masih added: 'So far, the hardline news organziations have attacked me. Fars News Agency, a semi-official news outlet affiliated with the Revolutionary Guards, has denounced the page and accused me of working with Iran’s enemies to promote promiscuous behavior.'
Iran's President Hassan Rouhani last year signalled an easing of restrictions against women who forgo the hijab in response to Basij - 'morality police' - who patrol Iran's streest for loose hijabs during the hot summer months.