Officers want to speak to anyone who was travelling on the A4042 between 11.45am and 12pm on Monday 7 August.
Gwent Police received a report of a road traffic collision on the A4042, southbound between the McDonalds and New Inn roundabouts at around 11.50am on Monday 7 August.
Officers attended, along with personnel from the Welsh Ambulance Service and South Wales Fire and Rescue Service.
The collision involved four cars: a Peugeot, a Ford and a black Mercedes and a grey Mercedes.
The passenger of the Ford, a 79-year-old woman, was taken to hospital where she later sadly died.
Her next of kin have been informed and are being supported by specialist officers.
Four other people were taken to hospital for treatment – their injuries are not thought to be life-changing or life-threatening.
Officers investigating the collision want to speak to any motorists who were travelling on the A4042 between 11.45am and 12pm on Monday 7 August or anyone with dashcam or CCTV footage to contact Police
Call 101, quoting log reference 2300262994, or send Police a direct message on social media.
