At the community centre, the trio will spend time with retired members of the rescue services who responded in the aftermath of the collapse, among them a 96-year-old woman who served as a police officer at the time.
An exhibition documenting the scale of the emergency operation will be on display, alongside representatives from the police, fire service, St John Ambulance, the British Red Cross and other organisations involved in the response.
The royals will also meet those most directly affected by the tragedy, including survivors, parents who lost children, former classmates and siblings of the dead.
Members of the Aberfan Wives, a group founded to support mothers bereaved by the disaster, will be among those present, along with representatives of the Ynysowen Male Voice Choir, which was established after the catastrophe as a means for local men to process their experiences together.