Today is the day that London Underground celebrates 150 years of operation. On 9 January 1863, the first underground journey took place between Paddington and Farringdon on the Metropolitan Railway. Regular passenger services started the next day, and Londoners have gone underground in their millions since then. But is the Metropolitan Line a true ‘underground’ line? And how did its northern most terminus end up just a few miles from Milton Keynes?

Paddington Station is the least central of all of London’s great railway termini. If you take Charing Cross as the centre of London (and, for many uses, it is the official centre of London), Paddington is the furthest out by almost half a mile. It is also in a peculiarly inaccessible part of London, tucked away behind a maze of residential streets and squares and the vast St. Mary’s Hospital. Confusing one-way systems and the complex junctions of the Westway help to exacerbate the sense of isolation.

If you have ever tried to get to Paddington by foot or on bike, you’ll know what an infuriatingly difficult place it is to reach. Even the Underground seems to serve it begrudgingly – the Bakerloo and District/Circle lines do not deign to share the same part of the station as the Hammersmith and City. The contemporary Metropolitan line contemptuously cocks a snoot at both Paddington and Marylebone, darting northwest just after Baker Street. As if to make sure its trains are not caught anywhere near these mainline stations the Met does not stop again until Finchley Road.

This seems particularly strange given that the Metropolitan Line’s raison d’être was to connect the Great Western Railway’s relatively new and grand 1854 station at Paddington with the City of London. This particular quirk is explained by the fact that the Hammersmith and City Line was originally part of the Met, and the current Met line is only a small section of an older purple empire.

The Metropolitan Underground Railway Line, running between Paddington and Farringdon and the world’s first underground passenger railway, was opened to the public on 10 January 1863 – exactly 150 years ago tomorrow. Transport for London along with a legion of train and Tube enthusiasts will celebrate the Underground’s first 150 years this month and throughout the year.

London Paddington had served as the London terminus of the Great Western Railway since 1838. For the first 25 years of its life, passengers faced a long schlep into town as a block of carts, cabs and omnibuses turned the New Road (today’s Euston Road) into an increasingly immobile three miles of traffic. To many Victorians, for whom daring feats of engineering were marvellous challenges and opportunities, the obvious answer was to tunnel beneath the streets.

The idea of a subterranean railway had a long gestation, with something similar to the Metropolitan Railway being first suggested in the 1830s. It would take decades of increasingly gridlocked streets and the real prospect of commercial stagnation before the City elders and the Establishment consented to the radical proposal. Much of the praise for getting the scheme off the drawing board and underground belongs to Charles Pearson, the Solicitor to the City of London and a great force of nature in the mid-nineteenth century metropolis.

The Metropolitan Line has ever since retained a sense of separateness from the rest of the network. With only six miles of its total 42-mile length going underground, the Metropolitan Line soon became a suburban railway with a useful underground connection into the City. It reaches far out into the countryside, with four stations outside of the M25 (the only other line with a similar boast is the Central Line, which has just one – Epping).

The Metropolitan Line was quick to realise that property could become its prime asset and its promotional department assiduously advertised ‘Metro-land’, a vast swathe of northwest London extending into Buckinghamshire, Hertfordshire and Middlesex. The company published ‘Metro-Land’ annually from 1915 to 1932, evoking the idea of a rural bliss within easy reach of London and where every family could have their own home and garden.

Metro-land would later be immortalised in the poetry and film of John Betjeman, the “hymnologist of Metroland”. The BBC documentary, ‘Metro-land’, saw Betjeman celebrate suburban north-west London. He visited sites on the length of the historic Metropolitan Line, which therefore saw him take in the furthest reaches of the Met’s ambitious network.

Verney Junction is a hamlet lying between Bicester, Milton Keynes and Buckingham, closer to the latter and no more than 20 miles from Oxford. It is in north Buckinghamshire and is set amidst rolling fields in a prime swathe of arable land. It is quiet, rural and, quite amazingly, was the northern terminus of the Metropolitan Railway until 1936.

What was the Metropolitan Line doing so far from London and in an area so remote and isolated that the station had to be named after the landowner for want of any other settlement nearby? The answer lies in the ambitions of the line’s chairman, Sir Edwin Watkin.

Watkin was also the chairman of the Manchester, Sheffield and Lincolnshire Railway (MSL&R), a railway which, as Andrew Martin splendidly puts it in Underground, Overground: A Passenger’s History of the Tube: “duplicated other railways’ routes in an inchoate way between Manchester and Grimsby, and generally stumbled about the north”.

The dash northwards to Verney Junction was therefore designed to provide access to London across railways controlled by Watkin. The MSL&R was renamed the Great Central Railway and would eventually emerge in the capital almost apologetically at Marylebone. Marylebone is not a great London terminus – John Betjeman described it as looking like a branch public library. The railway was not particularly successful, but did demonstrate the boundless ambition of its chairman.

The final, unrealized vision of this ambition could have seen the Metropolitan Line as a feeder to a cross-Channel tunnel. Watkin was the chairman of the South Eastern Railway and the Chemin de Fer du Nord. The only thing blocking him from sending non-stop services from Manchester and Sheffield to Paris via London was the English Channel. He did not see this as an insurmountable obstacle, and established the Submarine Continental Railway Company in 1882 to start exploratory work.

Only a lack of funds and a public outcry at the possibility of a French invasion stopped the work. A century would pass before a serious attempt at a Channel Tunnel was attempted. This time, the only connection to distant lands that the Met can offer is a stop at St. Pancras International, where the High Speed One line would whisk Eurostar passengers towards the Tunnel and Europe.