Those without tickets for the Champions League final are being urged not to drive or use public transport in Cardiff as the city braces itself to welcome “an unprecedented influx of visitors”.

The Welsh capital, which is hosting the biggest event in its history, is expecting 170,000 visitors for Saturday evening’s clash between European giants Juventus and Real Madrid.

.@swp_ucl out in force today ahead of tomorrow's Champions League final. Lots of officers patrolling the streets, all friendly & chatty pic.twitter.com/xSzXVWEGyg — JohannaCarr (@JohannaCarr) June 2, 2017

Assistant chief constable Richard Lewis, of South Wales Police, which is heading up a massive multi-agency security operation, said: “We continue to advise people who don’t have tickets to the match to avoid travelling by car or public transport to the city centre due to the unprecedented influx of visitors we are expecting.

“For those who have tickets, our advice is to allow extra time for travel and security checks.”

Up to 2,000 police officers will be patrolling the streets of Cardiff on Saturday, many having been brought in from other forces across Wales and the rest of the UK.

Lots of people heading to the football festival in Cardiff Bay as Lloyd George Ave is pedestrianised for a day #cardiff2017 #uclfinal2017 pic.twitter.com/rhk98hu2KW — JohannaCarr (@JohannaCarr) June 3, 2017

Mr Lewis said each officer was “fully aware of the huge task ahead and committed to ensuring residents and visitors to the capital have a safe and enjoyable experience”.

He also reminded members of the public to “remain vigilant throughout the day”.

While there may be thousands of supporters yet to arrive, by lunchtime on Saturday Cardiff was already buzzing with visitors.

The sun was shining – sort of – and thousands made the trek to Cardiff Bay, where the Champions Festival is being held, along Lloyd George Avenue, which has been pedestrianised for the day and is one of many city-centre road closures.

Most were wearing something to signify their allegiance – a scarf, banner, flag or shirt – and many stopped intermittently to chant or sing.

One police officer said: “They’re causing absolutely zero trouble.”

We made our way down to the festival earlier – allowing lots of time to pass through the bag search. Look how happy we are about it! pic.twitter.com/44D66TSZKl — Cardiff2017Travel (@Cardiff17Travel) June 3, 2017

The huge security operation was very much in evidence and there is no entry into the festival without a bag search.

Those with tickets for the match at the 74,500-capacity Principality Stadium – which will be renamed the National Stadium of Wales on the night as Uefa regulations ban the commercial title of a non-tournament sponsor being used – will not be able to take bags into the stadium but there will be bag drops around the city.

Officers are also trialling facial recognition technology at key locations to scan thousands of faces and match them in real time to people on pre-determined watch lists.

Real Madrid fans show their support in Cardiff prior to the Uefa Champions League Final (Nick Potts/PA)

South Wales Police said the first arrest was made with the help of the technology on Wednesday and was of a local man, not connected to the football.

A spokeswoman said: “The Uefa Champions League has clearly provided a perfect testing ground.

“While early indications are proving positive, we continue to develop our understanding of its capabilities and its limitations.”

Juventus fans in fine spirit (Nick Potts/PA)

The force is also continuing to investigate the theft of 13 final tickets from a hotel near Cardiff Airport on Thursday night.