A five-mile queue to see the Queen lie in state opens on Wednesday as “unprecedented” crowds descend on London.
The line will back up to Southwark Park in the south east, wiggle along the Thames’ south bank, cross Lambeth Bridge and double back to 14th Century Westminster Hall.
Mourners must keep moving and will get wristbands to buy food from 24-hour cafes, use portable loos or fill water bottles for free.
No10 refused to rule out 17 to 35-hour waits.
Reports claimed only 350,000 people would fit past the Queen’s coffin between 5pm on Wednesday and 6.30am on Monday - leaving hundreds of thousands disappointed.
No10 denied there was an “upper cap”, but the queue will close early to ensure those in line have the best chance to get to the front.
The PM’s spokesman said: “We want as many people as possible to be able to come… This is a significant period for the UK.”
A second shorter queue will run for disabled or vulnerable people, who can obtain a timed slot at the Tate Britain to enter the line.
Officials reportedly raised fears of people trying to “game” the second queue by faking illness. And the National Cyber Security Centre warned scammers “may seek to exploit” the Queen’s death by selling tickets for the lying-in-state. There are no tickets, and there is no charge to enter Westminster Hall.
The step-free route will be dotted by stewards with 1,500 soldiers on standby, police, Red Cross, St John’s Ambulance, Samaritans and more than 100 Scouts aged 18 to 25.
A "very limited" train service will run through the night on routes including Kent, Oxford and Southampton - but not on Avanti services to Manchester, Birmingham, Liverpool and Glasgow.
The Rail Delivery Group warned the city centre "will be exceptionally busy" with crowded Tube stations shut and mourners advised to walk.
A handful of die-hard royalists gathered on the south bank on Tuesday to secure their place - despite warnings to only start queuing on Wednesday.
Historian Anita Atkinson, 65, who has a museum dedicated to the royals in County Durham, said: “To be in her space was just electrifying, it's like some kind of goddess with an aura.”
Railway worker Sarah Langley, 55, joined the queue when she finished work on Monday and is back on duty at 6.20am on Thursday.
Speaking as rain began, she said: "It'll pass. It's not a big deal to wait 48 hours for someone who gave 70 years of their lives for us. It's a testament to how loved she was by everybody.”
Grandfather-of-16 Delroy Morrison, 61, from North London, said: “It doesn't matter to me, as long as my health is OK. It'll be fine, she spent 70 years looking after me."
Carer Monica Farag, 61, who grew up in the Philippines, said friends had pledged to bring her food adding: "It's OK, I brought lipstick and a comb."
David Chellet, 75, wearing a grey suit and black tie, said: “I don't know how I'm going to stay here for 24 hours but I must. I will find a way.
"The Queen has been all I've really known since I was five years old. She has sacrificed so much for me, this is the least I can do."
Here’s what you need to know.
How long will the queue last? MPs have been warned the queue could take 30 hours to get through, while another briefing estimates 17 to 35 hours. The government does not know for sure, saying only that it will be “very long” and involve queuing overnight.
Where do I join the queue? The back of the queue will move around depending on how full it is. It will be somewhere on the south bank of the River Thames and could be as far east as Southwark Park. Live updates on the location of the back of the queue will be posted on Twitter at @DCMS.
Where do I get a wristband? When you reach the back, you will be given a coloured and numbered non-transferable wristband - a record of when you joined. This lets you leave the queue to use a toilet or get refreshments, then return to your place.
What if I need the toilet? Portable toilets are dotted along the route and are marked on the map above. People’s wristbands will allow them to return to the queue.
What if I need food or water? Cafes and food stalls will get extended 24-hour opening hours. Shakespeare’s Globe, the National Theatre, British Film Institute and Southbank Centre will open for “comfort breaks” overnight. There are water refill points marked on the map.
Can I camp? Full-blown camping will be impossible because the queue constantly moves. Some have brought folding chairs but these are banned from Westminster Hall, as are sleeping bags, blankets and other camping equipment. People are told not to bring gazebos or tents to the queue.
Will I get wet? After heavy rain on Wednesday morning Westminster is forecast to stay dry for most of the whole four-and-a-half-day vigil.
Can I sit down? There will be “very little opportunity” to sit down as the queue moves continuously. Welfare centres set up in church and community halls close to the route will provide tea and coffee and a place to sit.
Can a friend queue for me? No. Only those given wristbands at the end of the queue will be able to stay in the queue.
What if I’m disabled? A separate, shorter accessible queue will begin at Tate Britain where timed entry slots will be issued to enter a half-mile-long line, along Millbank. Go to the accessible kiosk at the Tate Britain. There will be limited capacity for the accessible queue each day, so entrance is not guaranteed. This is open to “those with a disability or long-term condition which means they are unable to queue for an extended period of time.”
My partner is disabled. Can I go in the short queue with them? Yes, if you are eligible “you may be accompanied by one carer or companion”.
When’s the latest I can join the queue? Not known, but it will close early - i.e. before 6.30am on Monday - to give those in the queue the best chance of getting to the front.
Can I take photos? In the queue there are no restrictions. Photography in the Palace of Westminster is banned.
Do I need ID? No, there is no suggestion you need to bring ID to queue.
Do I need a ticket or to pay? No, the lying-in-state is not ticketed and there is no fee.
Could I get thrown out of the queue? Yes, if there is “queue-jumping, excessive consumption of alcohol or drunken behaviour”.
Can I bring my dog? Guide dogs, hearing dogs and other official assistance dogs will be permitted in Westminster Hall, but other pets are banned.
Can I bring my kids? It is not banned but parents are asked to bear in mind that the queue will be very long, possibly last overnight, and have very little opportunity to sit down.
Where can I drop my bag? The bag drop area for bags bigger than 40x30x20cm will be next to Lambeth Palace, but will delay your progress in the queue as it’s a slight diversion. It also has limited capacity so you could have to wait for space to free up.
Who will get to skip the line? Some dignitaries including MPs, who work in Westminster. There is not thought to be a skip-the-line ability for veterans or key workers. Disabled people get time slots (see above).
What should I bring? The government recommends you bring weather-proof clothes, food and drink to have in the queue, a phone charging bank and essential medication or equipment.
What items are banned? In Westminster Hall itself water, food, flowers, sharp items, banners, flags, non-foldable pushchairs and bags over 40x30x20cm will be banned. So are non-clear flasks for liquid, soft toys, photos, personal defence sprays, spray paint, padlocks, chains, climbing gear, fireworks, air-horns, flares, whistles, laser pens, placards, banners, advertising messages, coolers and hampers.
What should I wear? ‘Appropriate’ clothing without political or offensive slogans but there is no requirement to dress all in black.
Shall I just watch it at home instead? The BBC ’s red button service will provide a live feed from Westminster Hall and ITV and Sky will be running extensive coverage. It’s up to you.
