The British Way of Building Rapid Transit
By a more than 2-1 vote among my Patreon backers, the third installment in my series about national traditions of building urban rail is the British one, following the American and Soviet ones. While rapid transit in Britain outside London is even smaller than in the US outside New York, the British tradition is influential globally for two reasons: first, Britain invented the railway as well as urban rapid transit, and second, Britain had a vast empire much of which still looks up to it as a cultural and scientific metropole.
Nonetheless, despite the fact that all rapid transit traditions technically descend from London’s, it is worthwhile talking about the British way. What London built inspired and continues to inspire other cities, but many, mainly in the United States, Japan, and Continental Europe, diverged early, forming distinct tradition. As I noted in the post about the Soviet bloc, Moscow was heavily influenced by British engineering, and its own tradition has evolved separately but began as a more orderly way of reproducing the London Underground’s structure in the 1930s.
In taxonomy, this is called a paraphyletic group. Monophyly means a taxon descending from a single ancestor, for example mammals; paraphyly means a taxon descending from a single ancestor excluding certain monophyletic subgroups, for example reptiles, which exclude mammals and birds, both of which descend from the same common ancestor.
The invention of rapid transit
Like most other things Britain became known for, like constitutional government and colonialism, rapid transit evolved gradually in London. Technically, the first railway in London, 1836’s London and Greenwich, meets the definition of urban rapid transit, as trains made some local stops, ran every 20 minutes, and were grade-separated, running on brick arches. However, it is at best an ancestor of what we think of as rapid transit, since it lacked the really frequent stops of the Underground or the New York els.
The first proper rapid transit line in London, the Metropolitan line, opened in 1863. It, too, lacked some features that are standard on nearly all rapid transit systems today: most importantly, it was not self-contained, but rather had some through-service with intercity rail, and was even built dual-gauge to allow through-service with the Great Western Railway, which at the time had broad gauge. Trains ran every 10 minutes, using steam locomotives; to limit the extent of smoke in the tunnels, the line was not fully underground but had a long trench between King’s Cross and Farringdon.
The Met line and the second Underground line, 1868’s District line, were both built cut-and-cover. However, whereas Met line construction went smoothly, the District line had to carve a right-of-way, as the city did not have adequate wide streets for serving the proposed route. The areas served, Kensington and Chelsea, were even then a tony neighborhood with expensive real estate, and the construction costs exploded due to land acquisition. In today’s terms the Met line cost about $32 million per kilometer and the District $90 million, a record that among the historical lines I know of remained unbroken until New York built the Independent Subway System in the 1930s.
The Met and District met to form a circle, and in general, London loved building circular lines. In addition to what would be called the Circle line until a revision last decade, there were two circles farther out, called the Middle Circle and Outer Circle. These were run by mainline railroads; there was still no legal distinction between the two urban railroads and the mainlines, and through-service and even some freight service continued on the Met well into the 20th century, which the company used as an excuse to delay its merger with the other Underground companies.
Even electric rapid transit took time to take shape. After the bad experience with the District line, there was no more cut-and-cover in Central London. The next line to open, 1890’s Northern line, required the invention of deep boring and electric traction; it was not the first rail line to use electricity, but was the first excluding streetcars. However, while the line looked like a normal self-contained rapid transit line, it was pulled by electric locomotives; electric multiple units only came a few years later, starting haphazardly in Liverpool in 1893 (each car required separate controls) and in the more conventional way on the Chicago L in 1897.
Spontaneous order and radial network design
Among the inventions that came out of London was the radial network design. Unlike the physical inventions like underground rail and electric traction, this was not a deliberate choice. It evolved through spontaneous order, owing to the privately-funded nature of British railways. A British railway had to obtain the approval of Parliament to begin construction, which approval would also permit compulsory purchase of land along the way, but funding was entirely private. An early proposal for an underground railway, an 1860s route running what would later become the Charing Cross branch of the Northern line, was approved but could not secure funding and thus was not built.
The upshot is that with private planning, only the strongest lines were built. The strongest travel demand was to the center of London, and thus the lines were all radial, serving either the City of London or the West End. There was no circumferential service. While there were many circles and loops, these were conceived as reverse-branches allowing some railroads to access multiple Central London terminals, or as ways to join two radials like the Met and District without having to go through the difficult process of turning a train underground in a world in which all trains had to be pulled by locomotives.
The same preponderance of radial lines can be seen in other privately-planned contexts. Today, the best-known example is the matatu network of Nairobi. It is informal transit, but has been painstakingly mapped by urbanists, and the network is entirely radial, with all lines serving city center, where the jobs requiring commuting are.
Despite the private planning, London has only a handful of missed connections between lines: it has eight, but only one, between the Met line and the Charing Cross branch of the Northern line, is a true miss between two lines – the other seven are between parallel outer branches or between two lines that intersect a few times in close succession but only have one transfer (namely, the Bakerloo and Met). This is not because private planners build connections spontaneously – Parliament occasionally demanded some minor route changes, including interchange stations at intersections.
The role of regional rail
Like rapid transit, regional rail evolved in London in a haphazard fashion. The London and Greenwich was a mainline railway and the Met line had some mainline through-service, and even the deep-level tube lines are compatible enough with mainline rail that there is some track-sharing, namely between the Bakerloo line and the Watford DC line. The trench between King’s Cross and Farringon was widened to four tracks and turned into a north-south through-route in the 1870s but then abandoned in the 1920s and only reactivated in the 1980s as Thameslink.
The upshot is that London ended with the bones of a regional rail network but no actual service. The ideal was self-contained Underground lines, so even when connections suggested themselves they were not pursued. For example, the original proposal for an underground line between Euston and Charing Cross involved some through-service to the railways at both ends, but when the line was finally built as the Charing Cross branch of the Northern line it was not connected to the mainline and only took over minor branches in suburban North London.
While British planners did eventually plan for through-service – plans for Crossrail date to World War Two or just afterward – by then London was not innovating but rather imitating. By the war, Berlin had already had two S-Bahn through-lines, Munich was planning one, and Tokyo had three. The modern design for Crossrail is best compared with the RER A, in a city London has treated as its primary competitor for a long time now.
Exporting London’s network design
Moscow was heavily influenced by London early on. Later on, Singapore and Hong Kong both drew on British engineering expertise. London’s status as the first city to build rapid transit may have influenced Moscow, but by the 1920s New York had surpassed it in city size as well as urban rail ridership. Moscow’s drawing on London was as I understand it accidental – the chief engineer happened to have London connections – but in Singapore, Hong Kong, Australia, and so on the relationship is colonial, with extensive cultural cringe.
In all of these non-British cities, the British design as exported was cleaner. What I mean is, the systems have a radial structure like London, but the radii are cleaner in that two lines will generally cross just once, especially in Moscow; it’s not like London, where the Central line is always north of the District line, meeting once in a tangent at Bank and Monument, or where the Victoria line and Northern line cross twice.
Another cleaner aspect is the transfer experience. Singapore and Hong Kong both make extensive use of cross-platform transfers between otherwise perpendicular lines; London only does sporadically, on the Victoria line.
A third aspect is uniformly wide interstations. London’s average interstation is about 1.25 km, which is what I think of as the standard because it is very close to the average in Tokyo and Mexico City as well, and at the time I started tracking this statistic in the late 2000s, the Chinese systems were still small. Moscow’s average is 1.7 km, and Singapore’s is similar. Hong Kong is actually divergent there: the MTR mixes core urban lines averaging about the same as in London with the more widely-spaced historically mainline East and West Rail lines and the airport express.
The relative paucity of circumferential rail is hard to judge in the export cases. Moscow came up with the idea for the Circle Line natively; there is an urban legend that it was accidentally invented by Stalin when he left a coffee cup on the map and it stained it in the shape of a circle. Hong Kong doesn’t have much circumferential rail, but its geography is uniquely bad for such service, even more so than New York’s. Singapore does have a Circle Line, but it’s one of the two worst-designed parts of the MRT, with a reverse-branch (the other one is the self-intersecting, connection-missing Downtown Line).
At the same time, it’s worth viewing which aspects British-influenced systems are getting rid of when designing cleaner version of the Underground. The most important is regional rail. Singapore has none: it has a legacy narrow-gauge rail line to Malaysia, but has never made an effort to take control of it and develop it as an urban regional rail line.
Another negative aspect exported by London is the preponderance of deep boring. I made the same complaint when discussing the Soviet bloc: while London is poor in wide arterials that a cut-and-cover subway could go underneath, Moscow is rich in them, and the same is true of Singapore.
Does this work?
London invented rapid transit as we know it, but it did so gradually and with many seams. In some sense, asking if this works is like asking if rapid transit as a technology works, for which the answer is that it is a resounding success. But when it comes to the details, it’s often the case that London has accidental successes as well as accidental mistakes.
In particular, the fact that London almost invented regional rail is a source of endless frustration and extensive retro-crayon. The Met line is almost a 19th-century Crossrail, the Widened Lines are almost a 19th-century Thameslink, and so on. Instead, as time went on the trend has been toward more self-contained lines, which is good for reliability but not when there are self-contained slow tracks of mainlines to hook into, as is planned for Crossrail and as has sporadically been the case for the Watford DC line.
The British focus on radial systems has generally been good. To the extent London has underused metro lines, it’s not because they are poorly-routed as some of the lines in Paris are, but because they serve areas that have many urban rail lines and not a lot of population density; London is not a dense city, going back to the Victorian era, when it standardized on the rowhouse as the respectable urban housing form rather than the mid-rise apartment of Continental Europe or New York.
To the credit of British-influenced planning, Singapore has managed to fit a circumferential line into its system with good connections, just with an awkward reverse-branch. London’s own circumferential transit, that is the Overground, misses a large number of Underground connections due to its separate origin in freight bypasses and mainline rail reverse-branches, where Parliament saw no point in requiring interchange stations the way it did on the Tube. However, the cleaner version seen in Singapore only misses connections involving the Downtown Line, not the Circle Line.
What is perhaps the worst problem with the British style of design is the construction cost. The Northern line was not expensive – in today’s terms it cost around $35 million per km, give or take. However, after WW2 a gap opened between the cost of cut-and-cover and bored metros. The Milan method for cut-and-cover built a subway for around $45 million per km a few years before London bored the Victoria Line for $110 million. Britain exported its more expensive method, which must be treated as one factor behind high construction costs in Singapore, Hong Kong, Australia, and New Zealand; in New Zealand the regional rail tunnel is expensive even as electrifying the system was not.
In the future, cities that wish to build urban rail would be wise to learn from the network design pioneered by London. Urban rail should serve city centers, with transfers – and as in the subsequent refinements of cities that adapted London’s methods to their own needs, there should be some circumferential transit as well. But if mainlines are available, it would be wise to use them and run trains through on the local tracks where available. Moreover, it would be unwise to conduct deep boring under wide streets; elevated or cut-and-cover construction is well-suited for such avenues, causing some street disruption but producing considerable less expensive lines.






