The queue to see the Queen lying in state has reached a wait time of 14 hours with the government warning entry could be paused.
The line to get into Westminster Hall is currently nearly five miles long, with Southwark Park listed as the nearest landmark.
The park is “extremely busy” and close to capacity, the Department for Digital, Culture, Media and Sport (DMCS) said.
As of 9.08am, it tweeted: “Southwark Park is extremely busy. Entry to the queue will be paused if it reaches capacity.
“If you are planning to join, please consider waiting until numbers have reduced.”
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For most of the night the line was nearly five miles long, with Southwark listed as the nearest landmark.
By 8.15am it had reached 4.9 miles (7.9km) long.
Firefighters gave out bottles of water along the route while volunteers from the Samaritans were available and stewards, police and portable toilets lined the route.
Watch live stream of the Queen lying in state
Mourners spoke of “breath-taking” serenity in Westminster Hall where “you could hear a pin drop”.
PhD student Fiona Holloran wept after paying her respects.
The 34-year-old Londoner said: “It was very moving to see the vigil around her – I was a little bit surprised at how much it struck me.”
She had queued with her baby strapped to her in a carrier but said the wait had been “worth it”.
“It’s lovely that everyone has just a moment to themselves – no one was pushing,” she added.
Amy Harris, 34, said the atmosphere in Westminster Hall was “breath-taking”.
“When you’re able to go in and have a moment to look at it and reflect, the serenity of it – to be able to pay your respects in such a serene place, it’s very peaceful,” she said.