Southport, a quiet seaside town in northwest England, drew a global spotlight on July 29 when three girls were stabbed to death and other children were seriously hurt in an attack on the summer holiday event.
Rioting then broke out days later.
On their visit on Thursday, William and Kate, the Prince and Princess of Wales, spoke privately with families of the victims and a dance teacher who was present at the time of the attack, and later met representatives from local emergency services who had responded to the incident.
It was one of the first engagements Kate has carried out since she began to slowly return to work after ending her course of preventative chemotherapy for cancer, and it was her first in public since then.
"Today, the Prince and Princess of Wales visited Southport to show support to the community and hear how local people have come together as the town recovers from the tragic knife attack that took place," their office, Kensington Palace, said in a statement.
Kate's unexpected appearance came because the couple wanted to visit to show their support to the families and community, and let them know they had not been forgotten.
Prince William and wife Kate expressed concerns for the mental health of first responders. (AP PHOTO)
The visit echoes one made by William's father King Charles who went to Southport in August where he met some of the surviving children and their families.
Disinformation spread on social media in the aftermath of the July attack wrongly identified the assailant as an Islamist migrant, and led to violent clashes between protesters and police in Southport, and an attempt to attack the town's mosque.
A teenager, who was 17 at the time of the incident, has been charged with carrying out the murders.
Days of similar rioting followed across the country which police and the government blamed on far-right thuggery, leading to about 1500 arrests and almost 400 people being jailed as the authorities sought to stamp out the trouble.
