Three-and-a-half years late, the Elizabeth line is open for business.
The air conditioned, spacious purple trains began ferrying commuters and tourists beneath central London this morning (Tuesday, May 24), between Paddington in the west and Abbey Wood in the east.
Eventually, trains through central London will travel as far as Reading in Berkshire or Shenfield in Essex, when the new £19bn Crossrail project reaches completion.
But did you know there were plans to build Crossrail lines in Hertfordshire, and that some of these plans are still on the table?
The Superlink
Crossrail has a decades-long history, and the term "Cross-rail" emerged nearly 50 years ago in 1974.
It wasn't until 2001 that Transport for London and the government's Department for Transport put their heads together to form the Cross London Rail Link company to promote the idea.
But a challenger soon emerged - Superlink.
The idea would have seen trains speed beneath London from towns and cities throughout the southern and eastern England, including Watford, Cambridge, Stansted Airport, Ipswich and Northampton.
But the Crossrail company threw out the idea in 2005, citing "poor punctuality" on train lines in the countryside, and a price tag 1.5 times the size of the Elizabeth line's.
Watford and Tring
By 2008, Crossrail received the go-ahead from the Houses of Parliament, and just three years later - in 2011 - Network Rail mooted a plan to build a new branch of Crossrail out towards Watford and Tring.
"Recommended for detailed investigation, for several reasons," a company report read.
"To provide direct trains from this corridor to the West End, City of London, and locations such as Canary Wharf, avoiding the need to change onto the London Underground system at London Euston."
A welcome relief?
Greg Dickinson of The Telegraph might say so.
"By some margin London’s most abhorrent railway station, there was never a question as to whether this soulless 1960s breezeblock would occupy the bottom place in our list," he wrote in a 2020 review of London stations.
Dickinson added: "Today the station concourse is a pit of purgatorial despair, peppered at every hour of the day with a thousand or more people waiting for their train to arrive."
Jonn Ellidge at City Monitor said of Euston in 2018: "It would be unfair to compare Euston to hell as it does at least present an opportunity to go to a better place (Manchester, say, or Glasgow)."
The plan to build a Crossrail extension to Watford and Tring, which would bypass Euston, was shelved in 2016.
At the time, a Department for Transport spokesperson said: "A review of the business case for this extension has been explored and concluded the cost currently does not represent good value for money.
"However, the Metropolitan line will be extended to Watford Junction by 2020 and will allow trains to run to central London every 10 minutes in peak hours."
But the Metropolitan line was not extended to Watford Junction by 2020. That was also shelved - in 2018.
Crossrail 2
A second Crossrail is still on the table.
The concept for a new route between Broxbourne in Hertfordshire to Egham in Surrey was launched by Transport for London in 2015.
Grant Shapps, Secretary of State for Transport, forced Sadiq Khan to stop spending money on the plan in November 2020, when the Department for Transport bailed out TfL to the tune of £1.8 billion.
But Prime Minister Boris Johnson declared his support for the scheme at the official Crossrail opening on Tuesday, May 17.
He said: "The real thing for us now is to think about Crossrail 2, the old Chelsea-Hackney line.
"That is going to be transformative again. All the problems of commuters coming into Waterloo getting up to north London, you can fix that with another Crossrail.
"I think we should be getting on with that."
Trains would speed from Broxbourne and the Lee Valley into Dalston - which TimeOut hailed "inarguably one of the worlds coolest neighbourhoods" last year.
After a stop off at Euston St Pancras - a new "super hub" - and Tottenham Court Road to link up with the Elizabeth line, trains would surface again at Wimbledon.
Transport for London has not ditched the plan.
A statement after the 2020 funding deal read: "Crossrail 2 will still be needed in future to support London’s growth and we have clearly demonstrated the case for the scheme.
"The project has been put in good order, ready to be restarted when the time is right."
Is it all about London?
In a Welwyn Hatfield Times interview last week (Monday, May 16), Grant Shapps acknowledged that while London is getting a new line, Hertfordshire's east-west connections are "notoriously bad".
Mr Shapps believes his "revolutionary" plan for buses could ease the burden.
"Herts is one of only three areas in the country which wants to put in franchising - like London's system - so we could end up with a London-style service," he said.
"It's very exciting. It's experimental"
As well as a bus plan, Hertfordshire County Council is planning a rapid transit link between Hemel Hempstead and Harlow in Essex, through St Albans and Welwyn Hatfield.
A consultation on the Herts and Essex Rapid Transit (HERT) ended in January, and the council is preparing a "business case" to move the project forward.
A council statement reads: "The roads from Hemel Hempstead to Harlow already experience significant traffic congestion and poor journey time reliability.
"We are supporting the district and borough councils in planning for more than 100,000 new homes and more than 100,000 new jobs to meet our needs over the next 15 years."
But not everybody would like a transport "revolution".
Reader V Hall wrote to this newspaper lamenting the loss of Metroline bus 84 between Potters Bar and Barnet last week.
She wrote: "How is it that neither the Mayor of London nor anybody in government seems to be able to reinstate the vital Potters Bar to High Barnet bus route which was axed on April 2 this year?
"We don’t want to be 'revolutionised'.
"We just want our right to a decent, everyday bus service with its vital transport links."
Ms Hall added: "We urgently need some immediate 'levelling up' here in Potters Bar, starting with the reinstated bus service between Potters Bar and High Barnet."
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