The group captured the city in 2014, turning it into the capital of its self-declared "Caliphate".
The strikes on the wall allowed the forces to choose the best entry into the Old City, in order to avoid mines ISIS had laid.
The SDF is dominated by the People's Protection Units, or YPG, which Turkey views as an extension of the PKK, the insurgent group which has waged war with the Turkish government in the south-east of the country for years. Brett McGurk, U.S. special envoy to the coalition to defeat the Islamic State, announced the advance in a statement Tuesday on his Twitter account.
"SDF fighters would have been channeled through these locations and were extremely vulnerable as they were targeted with vehicle-borne IEDs ... as they tried to breach the Old City".
The operation was "a key milestone" in the campaign to "liberate the city", Brett McGurk, the USA envoy for the anti-ISIS coalition, said on his official Twitter account.
The group Raqqa is Being Slaughtered Silently says civilians are being placed in a desperate and impossible position.
It is believed 100,000 people are trapped in the city, which is defended by 4,000 ISIS insurgents who refuse to let the innocent bystanders leave.
Known as the Rafiqa wall, the structure is one of the last remaining monuments of the headquarters of the Abbassid caliphate, which was briefly seated in Raqqa before relocating to Baghdad.
The new deaths put at more than 200 the civilian toll from coalition raids on Raqa since the US-backed SDF entered the city last month.
As SDF forces have advanced, "Islamic State" (IS) has moved its command and control units to the city of Mayadin in eastern Syria, according to USA intelligence sources. The fight on the southern front began later this month.
"The market is fully under SDF control but [Daesh] is waging a counterattack", Abdel Rahman said. "The same civilians who are suffering indiscriminate shelling and summary executions by ISIL [Islamic State] are also falling victim to the escalating airstrikes, particularly in the northeastern governorates of Al-Raqqa and Deir ez-Zor", Zeid Ra'ad Al Hussein said.
Footage provided by the SDF showed their fighters roaming Qasr Al Banat, a historic quarter inside Raqqa's Old City.
"We may be counting casualties by the hundreds", he told AFP.
Soldiers stand guard at Raqqa city, Syria, 11 June 2017 (Issued 12 June 2017).