It's after the government re-imposed strict measures amid an increase in coronavirus cases in the country.
Mainland Spain and the Balearic and Canary Islands are covered by the quarantine rules and the Foreign Office is warning against all but essential travel to the mainland.
The strict new rules came into force at midnight on Sunday, just six hours after the news emerged on Saturday.
It meant many of the region's holidaymakers already in Spain were caught unaware.
Over the weekend, flights raced across European skies to land on UK soil ahead of the midnight deadline.
One flight from Fuerteventura to East Midlands Airport beat the deadline by just two minutes, meaning its passengers aren’t currently having to self-isolate for 14 days.
But, there’s confusion about what the new rules mean for those currently in Spain, or for those planning to fly there over the next few weeks.
So, what are the new restrictions, and what do they mean for would-be travellers?
Why are the rules being brought in now?
The Government said the move follows a “significant change” over the last week in both the level, and pace of change, in confirmed cases of the virus in Spain.
Figures from the World Health Organisation show that new confirmed cases almost doubled from 6th July to 13th July, when there were more than 9,000 across the whole of the country.
I’m already in Spain, should I come back as soon as possible?
No. People currently on holiday in Spain have been encouraged to follow the local rules, return home as normal and check the Foreign and Commonwealth Office’s (FCO) travel advice pages on gov.uk for further information.
The FCO is not currently advising those already travelling in Spain to leave at this time.
I’ve got a holiday booked to Spain, what should I do?
The FCO is advising against all but essential travel to mainland Spain.
The warning means that the travel insurance of anyone who travels to Spain in the future is invalid. But, if you travelled to Spain before the warning was announced on July 25th, your insurance will remain valid.
Consumer group Which advises customers to wait for your holiday company to cancel the holiday to claim a refund - don’t cancel it yourself.
While Abta – the UK’s travel trade association – has advised customers due to travel to the country imminently to contact their travel provider.
Are there still flights to Spain?
Ryanair is likely to do the same. If your flight isn’t cancelled, you won’t be able to claim a refund.
EasyJet said it planned to operate its full schedule in the coming days.
What about hotel bookings?
Hotels in Spain will remain open, which means you won't be able to claim a refund.
If you want to cancel, you’ll have to check the T&Cs of your booking.
Some online booking websites, like Booking.com and Airbnb, do offer last-minute cancellations on some listings.
Does the quarantine apply if the holidaymaker has been to a Spanish island?
Quarantine measures will apply to those returning from mainland Spain, the Canary Islands (Tenerife, Fuerteventura, Gran Canaria, Lanzarote, La Palma, La Gomera, El Hierro and La Graciosa) and the Balearic Islands, such as Mallorca and Ibiza.
But the Canary and Balearic Islands are exempt from the FCO advice against all non-essential travel.
Are other countries at risk of having new restrictions placed on them?
Health Minister Helen Whately said Spain had seen a "very rapid increase in rates" of coronavirus and warned the list of safe countries is kept "under review".
She said if other countries see rates "going up significantly and rapidly, we’ll need to take action".
Health Minister Helen Whately speaking this morning (27th July)
Consumer rights and travel groups have also been questioning why the so-called “travel corridor” with the UK’s most popular holiday destination was suspended with little notice, with the sudden turn of events catching out even Transport Secretary Grant Shapps, who is currently in Spain for his summer break.
According to The Sunday Times, Mr Shapps, whose department formally announced the rule change, had to dial in from Spain to discuss altering the guidance with Health Secretary Matt Hancock and Cabinet Office minister Michael Gove.
Where can I go instead of Spain?
It features popular short-haul destinations such as France, Italy, Turkey, Greece and Cyprus, as well as long-haul locations including Australia, Barbados, Hong Kong, Japan, New Zealand and Vietnam.
Fourteen British Overseas Territories are also included.
Portugal, the US, China and Thailand are among the notable absentees.
But, one Midlands travel agent warns that no matter where you go this year, there will be a risk:
Wendy Haines, travel agent from Rolleston-on-Dove
Can I claim statutory sick pay when I self-isolate after returning from Spain?
The government is relying on the goodwill of employers.
Foreign Secretary Dominic Raab said no worker following quarantine guidance should be penalised by employers, including by being put onto sick pay:
You could get SSP if you are unable to work and you’re:
self-isolating because you or someone you live with has coronavirus symptoms
self-isolating because you’ve been notified by the NHS or public health authorities that you’ve come into contact with someone with coronavirus
staying at home because you’re at high risk of severe illness from coronavirus – in other words ‘shielding’
You can get £95.85 per week of SSP if you’re too ill to work - it’s paid by your employer for up to 28 weeks.
And finally, when are things going to go back to normal for the travel industry?