Taking Afrin has been the main objective of Turkey's Operation Olive Branch, a ground and air offensive launched on January 20, with the aim of ousting the People's Protection Units (YPG), a Kurdish militia group.
Fighters waved flags and tore down the statue of a legendary Kurdish figure after claiming the city centre.
The Turkish military also released a statement saying the city centre was under control.
"Search operations to locate mines and other explosives are under way," the statement said as per The Guardian.
Further, the military posted a video on Twitter of a soldier raising a Turkish flag on a balcony.
"Now the Turkish flag will fly over there! The flag of the Free Syrian Army will fly over there!," Erdogan said at a ceremony marking the battle to open the Dardanelles during the first world war.
The two-month Turkish-led operation was aimed at ridding the border region of a Kurdish militia that Turkey considers a terrorist group.