Elizabeth line: The ambient detailing behind Crossrail's new stations

They are strikingly huge and wide-open spaces made from concrete. Futuristic but with just a hint of the Jubilee line about them.

These are London's new Crossrail stations. Many Londoners will be surprised at the cathedrals of transport that have been built below their city.

The detailing is very exact.

Close to the platforms, the stations are very, very similar. There is nice ambient lighting with only a handful of benches.

The concrete is dimpled and undecorated. Even the corners of the corridors have been designed to move people quickly.

Julian Robinson is the head architect for Crossrail and he has been showing me how they designed the curved corridor corners.

"We've taken advantage of the form of the engineering behind the sprayed concrete lining," he tells me.

"This has enabled us to express a smooth curve rather than what you would find typically on a London Underground-style of station, a right-angle junction.

"Because of the form of the construction, the benefit for passengers is of course as you are moving around and through you're constantly seeing there are no blind corners."

These stations are built to cope with population growth with capacity to spare. "It's like next generation," Julian explains.

"It's not a Tube line, it's a full-sized train. So part of the approach was, how do you address the difference in scale?

"How do you make the stations work and operate for large amounts of people and high volumes of people getting on and off the trains?"

Away from the platforms, on the surface a different architect has designed every station so they will all look different.

John Toovey is an associate architect with the company BDP. He designed the Crossrail element of Whitechapel station in east London.

He shows me how they have created a bridge into the station over the existing Tube tracks. It is light and airy and it has a green roof.

"We have taken the opportunity to include natural light on both sides," John says.

"As you come into the station from the entrance you can see where you're going immediately. It's very clear where you are going.

"It all happens in natural light as well, and naturally ventilated, so it all helps the wellbeing of the passenger."

The million-dollar question is when will Crossrail open? Bosses have said by the end of June at the latest.

There are lots and lots of dates flying around, but I'm told there are two potential dates.

Right now, it is all hush hush and nothing is confirmed officially.

Crossrail is over budget and very late - but the end is nearly in sight.

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