On May 24th, London will welcome its newest member to the family, the oldest underground railway in the world. In 1941, a dream that would only be realized in 2009, was first conceived. It is one of the biggest infrastructure projects in the western world, arriving several years late and over budget. It is hoped that this system will spur growth, relieve congestion on its Victorian-era network and remind the world of what Britain can do when it puts its mind to something. No pressure, then.

The London Underground was created from a railway boom, with competing companies building routes to serve the city's major economic hubs. Its many quirks are a result of nearly 200 years of politics, commerce, geography and geology. It has eleven lines, 272 stations and 250 miles of track, which is now under the auspices of a dedicated body, Transport for London.

Many of the lines were built to serve a smaller city than the present one. London is the center of gravity for a lot of the southeast of the country, not just the people living in its metropolitan area. It was for this reason that the green light was given to Crossrail, as both a way to relieve congestion on its tiny, Victorian-era tunnels, and to recognize how broad London's influence had become.

Image of Crossrail Rolling Stock at Old Oak Common.

The Great Eastern Main Line runs from the suburb of Shenfield, 35 miles northeast of London in the neighboring county of Essex. The Great Western Main Line runs through the city and then on to Reading, a large town 40 miles west of London. It is expected to serve 200 million passengers a year, increasing London and the south east's total rail capacity by around 10 percent. The tunnels that run through London itself are not part of the above-ground line.

It is hard to comprehend how there is space in this city for new stations and infrastructure. The gap between the existing Jubilee line tunnels and the new Crossrail tunnels is just two meters. A fleet of eight 1,000-ton Tunnel Boring Machines were tasked with weaving a new route through some of the most congested soil in the world. It's one of the reasons that the birth of Crossrail hasn't been easy, since you have hundreds of years worth of infrastructure that you can't touch during the construction.

Almost all of the seven million tonnes of material taken out of the ground was re-used. The soil was donated to the Royal Society for the Protection of Birds. This was used to build a nature reserve on Wallasea Island. In one instance, the rest of the clay soil was used to help build a golf course.

Image of a passenger being walked to safety along the Crossrail emergency escape route during trial running.

Between May 2012 and May 2015, 26 miles of tunnels were dug below the city. Konopka explained that the project was the biggest civil engineering project in Europe and produced the largest tunnels for the London underground. The Central Line has a diameter of around 11 feet, while the Crossrail tunnels have a diameter of around 20 feet.

Konopka said that there was some art and artistry baked into the system to help it run better. The railway line gently inclines in the tunnel sections approaching a station. That way, the train slows down since some of its forward motion is being diverted by the hill it has to climb. When you pull out of a station, the track is almost imperceptibly downward in order to give the train a quick departure.

It should be clear by now that Crossrail isn't a regular subway, even though it is an electric railway running under a city. It's not an official part of the underground, even though it features on the Underground Map. The Elizabeth line is the thing you will actually be riding. It is a railway unlike anything else in the UK because it connects to mainline stations at either end. The closest comparable is Paris, which has a series of lines that connect commuter suburbs to the city and then move people between stops in the city.

Southall platform, sign and boarding ramp.jpg

The project was designed to marry the old and the new into one seamless whole. Covid-19 was the other.

Colin Brown, Technical Director of the Crossrail project, says that the project is brilliant, but that it joins up to railways that were built in Victorian times.

Britain's railways use an antiquated signaling system to warn drivers of danger. After a series of fatal train disasters in the 90s, the system was updated slightly to improve safety, but is still a 20th century tool. The European Train Control System, also known as the ETCS, brings digital technology into the railways and promises a safer network. Crossrail had to play nice with its predecessors, even though it was built with the standard ETCS.

Communications Based Train Control (CTBC) is the signaling system used by the subway systems. The need for accurate location data and the density of trains under cities make it important to run services with small gaps between each train. While it is not a subway, Crossrail needs to behave like one while it is underground. The only system that can run the more subway-esque functions, like platform screen doors and tunnel vent interface, is CBTC.

The patchwork of systems wouldn't have been simpler just to pay to standardize the technology according to Brown. For a variety of reasons, it wasn't feasible, and so engineers have spent years finding ways to make the old and new, analog and digital, above-ground and below-ground systems work as one cohesive whole.

When it gets to Paddington, the train will be operated by an automatic system, with drivers acting as supervisors.

The timetabling systems are of paramount importance because the system is so much more complex. On the software engineering side, all of this information and calculation needs to be boiled down to a series of simple commands that a staffer can use to recover the service when things go awry.

The privatization of Britain's railways in the 90s was a problem that was forced to be addressed. The Government decided to franchise each region's railway operator instead of a centrally planned and operated railway. The project had to work with a variety of operators who ran different lines.

Some of that, you will never get away from the fact that an operator is key, regardless of how much information the system can give you. Lee Price is a former personal trainer and badminton coach who joined the company. Price's story is common among new Crossrail drivers, coming from outside the train driving profession rather than within. The project decided not to take drivers from other underground or mainline services in order to keep staffing levels the same. It helps bring the economic benefits of the system to more people, creating training and job opportunities.

Image of an unfinished tunnel at Woolwich station.

Price is a veteran of the service and trains other drivers, although he isn't yet rated for the entire route. It will only be after the central section is opened that drivers will be able to run back and forth on a regular basis.

The role of the train driver varies depending on the route the train is on.

The public will be able to use the services between Paddington and Abbey Wood on May 24th. On the day, the various arms of the service will be renamed to the Elizabeth line. 12 trains per hour will run along the line, starting at 6:30am and ending at 11:00pm each weekday, with a full service ramping up over time. Bond Street is one of the new mainline stations that has yet to open.

If the railway helps boost London's fortunes, it won't be long before people look forward to the next project. The proposed line would run from the northeast to the southwest of the city. It is designed to relieve congestion on journeys north and south of the city by joining up routes.

The project has been put on ice because of government funding cuts. The lessons learned from the slow birth of Crossrail are currently embedded in the team that is just finishing their work. It would seem like a criminal waste of resources to let that experience wither on the vine. There will be people asking why London deserves another expansion of its public transport network when other major cities don't. Politics, economics, geography, and geology will determine the future of the most famous tube in the world.