Rodi Said/Reuters
Fighters from the Kurdish-dominated Syrian Democratic Forces celebrating their victory over the Islamic State in Raqqa, Syria on Tuesday
After months of fighting, the US-backed Syrian Democratic Forces (SDF) have conquered Raqqa, the capital of the Islamic State's so-called caliphate and its last major stronghold in the Middle East.
But the victory by no means indicates that ISIS is defeated, and enormous ethnic challenges still lie ahead for the embattled country.
Here's how the Raqqa campaign was won, and what lies on the horizon for Syria: