Beyoncé fever is building in the capital as thousands of fans from across the globe gear up for the singer's gig.
One woman told our reporter Kate Lewis that she has been listening to Beyoncé's music every day since booking her ticket in January.
Kate Lewis reports from the capital
Doors at the Principality Stadium opened at 5:30pm and the first performance kicks off at around 7:30pm.
Pictures on social media show a packed stadium as fan Sian Blackham said: "Good evening Cardiff! Cannot wait for @Beyonce to entertain us."
Meanwhile, South Wales Police's facial recognition van will be in Cardiff city centre during the major event in the city.
The decision has been criticised by campaigners, who say it is an "outrage" that the CCTV van is being used.
However, it has not put a damper on the mood in Cardiff.
One fan told ITV News: "It's a once in a lifetime, she's only in Cardiff once."
Another said: "We work to support Beyoncé's tickets."
A picture of Cardiff central railway station posted on Twitter this morning showed the barriers out in preparation for thousands of fans catching trains home.
However, there are several road closures and diversion of traffic, and engineering works on many rail lines mean there are no trains running on some popular routes.
Replacement buses are running instead of trains on the Rhondda, Cynon and Merthyr Tydfil lines down to Pontypridd. Trains are running between Cardiff and Pontypridd but Transport for Wales said it expects these services to be "very busy".
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