RIYADH: Saudi Arabia allowed women to drive from Sunday, overturning the world's only ban on female motorists, a historic reform that is expected to usher in a new era of social mobility.
The move, which follows a sweeping crackdown on women activists who long opposed the ban, is part of Crown Prince Mohammed bin Salman's wide-ranging reform drive to modernise the conservative petrostate.
Women in the capital Riyadh and other cities began zipping around streets bathed in amber floodlights soon after the ban was lifted at midnight, some in cars with thumping stereo music.
"It is a historic moment for every Saudi woman," said Sabika al-Dosari, a Saudi television presenter before driving a sedan across the border to the kingdom of Bahrain.
The lifting of the decades-long ban, a glaring symbol of repression against women, is expected to be transformative for many women, freeing them from their dependence on private chauffeurs or male relatives.
"This is a great achievement," billionaire Saudi Prince Al-Waleed bin Talal said as his daughter Reem drove a family SUV, with his granddaughters applauding from the back seat.
"Now women have their freedom," he added in a video posted on Twitter.
Some three million women in Saudi Arabia could receive licences and actively begin driving by 2020, according to consultancy firm PricewaterhouseCoopers.
The kingdom earlier this month began issuing its first driving licences to women in decades, with some swapping their foreign permits for Saudi ones after undergoing a practical test.
A handful of female driving schools have cropped up in several cities, training women to drive cars as well as Harley Davidson motorbikes - scenes that were unimaginable even a year ago.
Many Saudi women have ebulliently declared plans on social media to drive for coffee or ice cream, a mundane experience elsewhere in the world but a dazzling novelty in the desert kingdom.
However, in a nation torn between modernity and tradition, many are also cautiously bracing for a backlash from arch-conservatives who spent decades preaching that allowing female motorists would promote promiscuity and sin.
The decision to lift the ban was catalysed in large measure by what experts characterise as economic pain in the kingdom owing to a protracted oil slump.
The move is expected to boost women's employment, and according to a Bloomberg estimate, add $90 billion to economic output by 2030.
Many women fear they are still easy prey for conservatives in a nation where male "guardians" - their fathers, husbands or other relatives - can exercise arbitrary authority to make decisions on their behalf.
The government has preemptively addressed concerns of abuse by outlawing sexual harassment, with a prison term of up to five years and a maximum penalty of 300,000 riyals (US$80,000).
Prince Mohammed, appointed heir to the most powerful throne in the Middle East a year ago this month, has also lifted a ban on cinemas and mixed-gender concerts, following his public vow to return the kingdom to moderate Islam.
But much of the initial optimism over his reforms appears to have been dented by a sweeping crackdown on women activists who long opposed the driving ban.
Authorities have said that nine of 17 arrested people remain in prison, accused of undermining the kingdom's security and aiding enemies of the state.
The detainees include three generations of activists, among them 28-year-old Loujain al-Hathloul -- also held in 2014 for more than 70 days for attempting to drive from neighbouring United Arab Emirates to Saudi Arabia -- and Aziza al-Yousef, a retired professor at Riyadh's King Saud University.
State-backed newspapers have published front-page pictures of some of the activists, the word "traitor" stamped across them in red.
Human Rights Watch last week said the kingdom has arrested two more women activists - Nouf Abdelaziz and Mayaa al-Zahrani, in what it denounced as an "unrelenting crackdown".
Even some of the prince's ardent supporters have labelled the crackdown a "mistake".
It has been seen as a calculated move both to placate clerics incensed by his modernisation drive and also to send a clear signal to activists that he alone is the arbiter of change.
"If the authorities give credit to the women who championed lifting the driving ban, it means conceding that reforms can be won through activism, and then the Saudis may demand more," said HRW researcher Rothna Begum.
"Saudi Arabia's crown prince wants it both ways: to be lauded as a reformer on the world stage, and to ensure his status as the only reformer at home."