Cornwall's services are struggling to deal with an influx of visitors.
With more Britons holidaying in the UK, Visit Cornwall estimates there are about 210,000 visitors, up from a usual peak of 180,000.
Beaches are busy, traffic heavy and the situation at the hospital is described as "dire" by its medical director.
Malcolm Bell, head of Visit Cornwall, said some "visitors are not getting a good experience, locals are frustrated and systems can't cope".
The county's only 24-hour Emergency Department - at the Royal Cornwall Hospital serves the 560,000 residents - has been incredibly busy, with waiting times often more than four hours.
Medical director Allister Grant called the situation "unprecedented".
The hospital said about 30% of those attending the Emergency Department are not registered with a Cornish GP, and were assumed to be visitors.
The number of Covid patients in the hospital has also increased, with 22 inpatients with the virus on 3 August.
South West Water said the demand in Cornwall was about 10 megalitres more water per day compared to this time last year, which was "the equivalent of between 50,000 to 75,000 people's water use per day".
The company said the demand is "putting a strain on the network" although reservoir levels are "looking healthy".
However, for plenty of business owners the economic boost is welcome after a difficult 18 months, with an estimated £1bn lost in visitor spending.
In Padstow, Cherry Painter from Cherry Trees cafe said it is "absolutely amazing. It's unprecedented - we have never had the crowds like this before. People realise this is where to come after lockdown. They are all enjoying themselves."
Many businesses are also facing staffing shortages exacerbated by those being contacted by the NHS Covid app and told to self-isolate.
Next door to Ms Painter, Richard Walker from Padstow Fish and Chips said: "We are up by about 25 to 30% on a normal peak summer season. But that is made even busier by the fact we have a significant lack of staffing so we are having to manage on much less staff than we would normally."
The Headland Hotel in Newquay has lost 21 staff in this way, causing it to close off some of its accommodation.
Increasingly, individuals have also been cashing in by letting their houses out to visitors, or opening a spare field as a pop-up campsite.
"Lots of local people, which you cant criticise them for have suddenly decided they can make a few thousand if they rent out their property and either go somewhere else or move in with mum and dad", Mr Bell said.
Ali Arnison arrived on Friday, 30 July, for a long-awaited week-long holiday in Newquay with six of her family. By Wednesday they had returned home to Leeds.
"There are so many cases of Covid down there, no staff in restaurants... but they're still packing people in.
"Ridiculously busy supermarkets with no staff and empty shelves. Even remote beaches were heaving, just no escape at all from the crowds. I feel so sorry for the locals."
She said they were disappointed to end their holiday early, but "safety comes first".
The latest figures show infection rates in Newquay West of 792.7 per 100,000 people, well above the averages for Cornwall of 248 and for England of 270.
When the sun was shining on Wednesday local people reported that Cornwall was "busier than ever".
In Perranporth, which has a resident population of 3,000, lifeguards estimated a peak of 14,000 people on the beach: "We don't get days like that very often."
The car parks, and their overflow sections, were full by mid-morning and people took to parking along any available route into the town.
This meant parking on verges, and in housing estates well away from the beach, and traffic jams winding for miles along the small roads and country lanes.
Tracy Brown has missed two cleaning jobs because of getting stuck in traffic this week but said: "I'm upset I have lost money after the last 18 months we have had, being self employed, but my biggest concern was the care in the community.
"Elderly people are sat in the beds waiting to be got up, given breakfast and even medication. But with a two-hour wait in traffic this is dangerous."
At Porthcurno in west Cornwall, and Porthcothan on the north coast, some beach goers returned to their vehicles to find tickets on their windscreens after a visit from Devon and Cornwall Police and Cornwall Council.
Penzance Police said: "Porthcurno was again brought to a stand still... due to inconsiderate parking by visitors attending the area."
It warned: "Inconsiderate parking like this may result in the delay of emergency services and put lives in danger."
Kim Hayward, from Porthcothan - a small village with a beach near Padstow, north Cornwall, said: "I've never known it as busy as it is at the moment.
"We welcome them with open arms but I just wish that when they came they had some consideration for other people.
"We put bollards around to stop them parking on the junction, but they have parked the other side of the bollards on the road which makes it even worse than it was before."
An anonymous caller to BBC Radio Cornwall said she and her husband "feel like prisoners in our own home" since a pop-up campsite was authorised next door to them for the first time this summer.
"It is so hectic. I can't cope with it," she added.
Mr Bell said: "The biggest factor is the restriction on travelling abroad which has meant that most if not all of the accommodation is full with the only vacancies coming when people cancel, or get pinged.
"This summer is a one-off but it is also a bit of a siren to say we can't be here again in normal circumstances."
Mr Bell said an anti-tourist feeling has been growing in recent years among people for whom Cornwall is home.
He thinks this can be partly put down to the 10,000 or more additional properties that are now available to let through online platforms like AirBnB.
"Up until about 10 years ago we were losing bed stock in Cornwall. In 2018-19 we were holding numbers but we weren't growing. And up until 2019 there wasn't that much anti-tourism feeling.
"We don't want to be here where the visitors aren't getting a good experience, the locals are frustrated and the systems can't cope."
In order to "reduce the peak and capacity in August", he wants every property being offered to let, to be officially registered "so we at least know what is going on".
He said without a reduction "we will end up in a place we don't want to go, a very dangerous place which is the quality of experience for the visitor will go down, the price will go down, and we will end up with over-tourism".
"The last thing I want to see is Cornwall being destroyed by tourism."