> In 1863, the world's first subterranean railroad opened in which city?And the answer: London.Photo credit: Londontopia.net.[https://londontopia.net/site-news/featured/tube-love-top-10-things-love-london-underground/]In 1863, the London Underground opened, and first featured steam engines thatrelied on coal, which created toxic fumes underground. Almost three decadeslater, in 1890, the first electric railway launched, running from King WilliamStreet in the City of London, under the River Thames, to Stockwell.Before its creation, the idea of a railroad stretching beneath the length ofLondon seemed the stuff of dreams. The public was beyond dubious – some localministers went so far as to accuse the railway company as trying to break intohell. The expense and logistics of the project painted it in an unsavory lightand, ultimately, few thought it would work. And yet, on January 10, 1863, 30,000 people ventured underground to travel onthe world's first subway: a four-mile stretch of line underneath London. Afterthree years of construction and many setbacks, the Metropolitan Railway was openfor business. London in the 1800s was deeply congested. Carts, costermongers, commuters andcows each jammed the road, making inter-city travel arduously time-consuming. Itwasn't until visionary Charles Pearson proposed the idea of railways under theground that things began to change. First using the "cut and cover" technique,workers dug a deep trench before constructing a tunnel of brick archways andrefilling the hole above the new tunnel. While this method was effective, it wasimpractical, as no rail lines could be built below buildings without requiringtheir demolition. Regardless of practicality, the Metropolitan Railway was wildly successful, andmany new rail lines came to life in the years following its inception. By thelate 1880s, however, the city had become too dense with buildings, sewers, andelectric cables for the cut and cover technique. Thus the Greathead Shield wasborn. This new machine could tear through the earth at deeper levels, and onlyrequired the control of 12 men. These new lines, or "tubes," didn't disturb thesurface and made it possible to dig under buildings. By the early 20th century, subway systems popped up in most major cities. Today,underground rails occupy a necessary space in most cities around the globe. Learn more about the world's first subway below.