Euro 2016: Violence threat 'unites' Wales and England fans
Wales fans have said it is "sensible" they stick together with England fans ahead of the Euro 2016 match between the two countries.
Tens of thousands of supporters are in Lille as the two teams prepare to play in nearby Lens on Thursday.
It comes as police have fired tear gas against fans in Lille, where Russian and Slovakian supporters also are.
On Tuesday, there were reports of isolated trouble involving Russian fans also in the city.
Adam Morgan, 27, of Mountain Ash, said the camaraderie between fans meant there was "less chance of trouble".
He said: "It's like the baby brothers have joined the older brothers to look after them.
"I think it's sensible. Hopefully it just means there is less chance of trouble between the two sets of fans."
Extra police were drafted in with concerns raised as Russia played Slovakia in Lille on Wednesday, with Wales and England fans also gathering there ahead of Thursday's game.
The city also saw trouble involving fans after Germany's win against Ukraine there on Sunday.
Steve Smolka, 35, of Llanelli, Carmarthenshire, said there had only been "little pockets" of trouble in the city but "nothing major".
"It's been very friendly, I think, between the England and Welsh fans.
"There's been a bit of trouble with the Russians but very small bits and pieces. Nothing too serious."
He said the police presence in the city had increased since Tuesday.
Barry Dobson, 69, of Radyr, said there had been "no problem whatsoever".
He said: "The atmosphere is absolutely superb.
"Everybody is excited, you can hear the singing and I'm very much looking forward to going to Lens tomorrow where it's going to be rocking."
A public drinking ban is in place in Lille, with no alcohol to be sold from off licences and supermarkets or drunk on the streets until Friday morning.
However, fans have already flouted the prohibition by drinking in streets and squares, according to Vince Alm, of the Football Supporters' Federation Cymru.
He does not think the ban is enforceable and said: "There are so many outlets around it's impossible.
"But alcohol I don't think is the main issue. The main issue is these Russian hooligans.
"They are not interested in drinking. They're just interested in turning up, having a fight and running off."
Nathan Jones, 25, of Mountain Ash, said it had been "surprising" to see English and Welsh fans chanting together on Tuesday.
He added: "I think it's united us against the Russians because of all the news."
BBC Wales' Gareth Lewis in Lens
The advice all along has been only to go to Lens if you have a ticket. And even if you do, get in and get out again.
But the atmosphere in this former French mining town could not be more relaxed, 24 hours before kick off in one of Euro 2016's highest profile matches.
It is a place proud of its heritage. Its 42,000-seater stadium was originally built by miners during the Great Depression and the local club AC Lens has punched above its weight ever since - the town only has a population of 36,000.
The locals we have spoken to think it is a shame fans have been told to stay away. But those that do come - and are already here - will get a warm welcome.
The "alcohol ban" seems open to interpretation. One bar owner told us it applied only to spirits while another that anything served in a plastic glass was fine and a third that drinking on the premises or at the pavement tables would be OK. Just 200m from the stadium, the manager at a cafe told us he would serve until the police told him not to.
Many Welsh fans here will feel at home. The stadium car park is on the site of a former colliery - another former pit now hosts a branch of the Louvre museum which attracts nearly a million visitors a year.
And a group of fans from another former British mining area - Nottinghamshire - were tucking into (plastic glass) pints on Lens' high street.
"The atmosphere here could not be more different to Marseille," one told me.
Nearby Lille is on high alert on Wednesday as Russia take on Slovakia.
"It is England and Wales, in it together," said another - ironic for a Wales v England game put in the "high risk" bracket by Uefa.
After Thursday's match Wales and England fans will go their separate ways. But in the back of Welsh minds will be their own match against Russia in Toulouse next Monday.