Raqqa has played a symbolic and strategic role in the rise of Islamic State since the jihadist group seized it almost three years ago.
It is the extremists’ de facto capital in Syria and has been used as a base to plan overseas terror attacks, including in France and Belgium.
Raqqa was the first Syrian city to be captured by IS, also known as Daesh, after it battled a coalition of rebel groups.
Foreign fighters, including dozens of Britons, flocked there, travelling mostly through Turkey, to live under the so-called caliphate declared by IS leader Abu Bakr al Baghdadi.
Some estimates put the total number of fighters in the city at 3,000-4,000. Raqqa was also home to almost 200,000 civilians, mostly Sunni Arabs.
IS is accused of carrying out horrific abuses in the city, including beheadings, hangings and the torture of prisoners as well as public floggings.
But military operations have now ended against IS in the city, the Syrian Democratic Forces group has said, with clearing under way to flush out remaining fighters.
Here are some key dates in Islamic State’s occupation of Raqqa
:: 14 January, 2014
Jihadists loyal to a group known as the Islamic State of Iraq and the Levant take control of Raqqa after fighting rivals including from the al Qaeda-linked al Nusra Front.
:: 10 June, 2014
The group takes control of Iraq’s second biggest city Mosul, before capturing large swathes of the country’s northwest.
:: 29 June, 2014
In an audio recording posted online, the group announces the establishment of a self-styled caliphate for the territories it controls in Iraq and Syria, and renames itself Islamic State.
IS chooses Raqqa as the centre of the caliphate. Such a state, where people live under strict Islamic laws, has been a goal for many jihadists.
:: 19 August, 2014
American hostage James Foley is beheaded reportedly by British IS militant Mohammed Emwazi, also known as Jihadi John. Mr Foley is believed to have been killed at a location in hills south of Raqqa.
He was among a number of westerners, including UK aid worker David Haines and taxi driver Alan Henning, held captive and later beheaded by IS, reportedly near the city.
28 September, 2014
Four British jihadists, believed to be based in Raqqa with IS, are hit with UN sanctions.
They are: Omar Hussain from High Wycombe, Nasser Muthana from Cardiff, Aqsa Mahmood from Glasgow and Sally Jones from Chatham, in Kent.
:: 21 August, 2015
British nationals Reyaad Khan and Ruhul Amin are killed in a drone attack on a car in Raqqa. Khan, from Cardiff, had reportedly been planning an attack during VJ commemorations in the UK that month.
12 November, 2015
Kuwaiti-born Mohammed Emwazi was killed in Raqqa in a drone strike which targeted a car he was in.
:: 15 November, 2015
French fighter jets launch bombing raids on the Syrian city, days after the jihadist group claimed co-ordinated attacks in Paris in which more than 130 people were killed.
The operation, carried out in coordination with US forces, struck a command centre, recruitment centre for jihadists, a munitions depot, and a training camp for fighters.
:: 5 November, 2016
US-backed militia groups, known as the Syrian Democratic Forces (SDF), made up of Kurds and Arabs, launch an operation to capture Raqqa from IS.
:: 4 December, 2016
Two IS members involved in planning the Paris atrocities were among three militants killed in an airstrike in Syria, the Pentagon said, adding the trio – Salah Gourmat, Sammy Djedou and Walid Hamman – were plotting more attacks on western targets.
:: 6 June, 2017
The SDF, backed by US airstrikes, enters opposition sides of Raqqa, seizing areas in the east and west of the city and cutting off the last IS escape route by the end of the month.
:: 29 June, 2017
In Mosul, Iraqi government troops capture a symbolic mosque from where al Baghdadi had proclaimed the IS caliphate three years earlier.
After the soldiers seized the structure, the country’s prime minister Haider al Abadi said it was the end of the “Daesh state of falsehood”.
:: 2 July, 2017
Around 1,000 extra SDF fighters are deployed to the front line in Raqqa amid reports of “extremely violent” clashes.
:: 4 July, 2017
SDF rebels penetrate the strategic Rafiqah Wall surrounding the Old City of Raqqa in a “key milestone” in the campaign to “liberate the city”, said US Central Command. A couple of thousand jihadists were believed to be making a last stand there.
:: 20 September, 2017
The IS strike cell that plans and encourages attacks on Europe has moved but still exists, Sky News has been told.
:: 12 October, 2017
Sky sources say British jihadist Sally Jones has been killed in a US drone strike in Syria.
Meanwhile, the SDF says it has taken control of 90% of Raqqa, with less than 400 IS jihadists remaining in the region.
:: 14 October, 2017
The SDF says it is engaged in a “final” battle to oust IS militants from the city.
:: 17 October, 2017
The SDF says military operations against Islamic State in Raqqa are over.
-SkyNews