People across England have had their first night out in three months, after coronavirus restrictions eased.
Hospitality venues such as pubs and restaurants as well as hairdressers, cinemas and theme parks reopened with strict social distancing rules.
But ministers urged caution and England's chief medical officer said the latest step was not "risk-free".
It comes as buildings and landmarks across the country were lit up to celebrate the NHS.
People were also encouraged to place lights in their window on Saturday to remember those who have died from the virus.
Image copyright AFP Image caption Buildings were lit up blue in honour of the tens of thousands of people who have died during the coronavirus pandemic in the UKDowning Street was lit up blue while other public buildings including Royal Albert Hall, Blackpool Tower, the Shard and the Wembley Arch were also illuminated.
Restrictions on the hospitality sector remain in place in Scotland and Wales, while pubs have been able to open in Northern Ireland since Friday.
In England, people are being allowed to stay the night away from home for the first time since lockdown started, with campsites and holiday accommodation also reopening.
Police in Dorset, Devon and Cornwall reported gridlock on the roads on Saturday - including a high volume of caravan owners heading to the coast.
Image copyright PA MediaDespite the relaxation of restrictions, some 30% of bars, pubs and restaurants have stayed shut, according to the Night-Time Industries Association, amid fears for safety and concerns over how to implement social distancing guidance.
Campaign for Real Ale national chairman Nik Antona said: "The government have not really been helpful with their guidance, leaving it to the last minute in a lot of cases." Some pubs "want to see what's going to happen" before opening their doors, he said.
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At a pub in Newcastle, punters enjoyed their first "proper pint" in more than three months. "The atmosphere is a bit different... that was expected. But everyone's having a good time," one customer told the BBC's Fiona Trott.
"The regulations are good and everyone is sticking with them, by the looks of things," said his companion.
But it is a very different sort of Saturday evening from pre-lockdown expectations. Customers are expected to book a table in advance, to register their details on arrival and to stay no more than three hours.
While pubs in Scotland remain closed one publican in Berwick-upon-Tweed claimed 70% of his pub's bookings were from over the border.
Publican Marc McDonald told BBC Scotland people had travelled from as far afield as Glasgow and Edinburgh to drink at The Meadow House.
Image copyright Getty ImagesIt is a different story in Leicester where the streets were largely deserted as pubs and other venues remain closed after the city became the first to be subject to a local lockdown on Monday, following a spike in Covid-19 cases.
Other rule changes that came into effect on Saturday include allowing two households to meet indoors or outside, including for overnight stays - although they have to maintain social distancing.
People in England are still urged to stay 2m apart, but the new "one metre plus" guidance means they can get closer if they use "mitigation" measures, such as face coverings and not sitting face-to-face.
Chancellor Rishi Sunak welcomed the reopening of businesses, saying it was "good news" people were working again.
On a visit to The Bell and Crown in Chiswick, west London, Mr Sunak said the almost half a million people who worked in Britain's pubs and bars were "helping us all to enjoy summer safely".
But Labour leader Sir Keir Starmer criticised the government's messaging as "all over the place", telling TimesRadio: "You have had some government messaging saying go out and have a drink, other messaging saying be responsible, be cautious - the messaging, I think, has been very poor over the last few weeks."
Image copyright Peter Dench/Getty ImagesDespite the easing of restrictions, public health experts are continuing to warn people to be cautious to avoid a second UK wave of the epidemic.
Prof Robert West, an epidemiologist from University College London, told the BBC: "We are looking at around 20,000 new infections a week and around 1,000 deaths a week and the rates aren't coming down very fast."
The latest figures, released on Saturday, showed a further 67 people had died in the UK after testing positive for coronavirus, bringing the death toll to 44,198.
How are you planning to deal with lockdown easing? Are you going to meet loved ones for the first time since it began? Are you working? Are you happy or concerned about lifted restrictions? Please email haveyoursay@bbc.co.uk.
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