One effect of this is that the centre of the town is normally a noticeably quiet and peaceful place in the evenings.One of the most prominent industries to arrive in the town in the early years was the manufacture of corsets: the Spirella Company began building a large factory in 1912, close to the middle of town and the railway station that opened the next year.
Letchworth was a relatively small parish, having a population in 1801 of 67, rising to 96 by 1901.
In 1898, the social reformer Ebenezer Howard wrote a book entitled To-morrow: A Peaceful Path to Real Reform (later republished as Garden Cities of To-morrow), in which he advocated the construction of a new kind of town, summed up in his Three Magnets diagram as combining the advantages of cities and the countryside while eliminating their disadvantages.
For example, the Garden City project would be financed through a system that Howard called "Rate-Rent", which combined financing for community services (rates) with a return for those who had invested in the development of the City (rent).
The book also advocated a rudimentary form of competitive tendering, whereby the municipality would purchase services, such as water, fuel, waste disposal, etc., from (often local) commercial providers.
Pubs that had existed from before the foundation of the Garden City continued – including the Three Horseshoes in Norton, The George IV on the borders with Baldock, and the Three Horseshoes and The Fox in Willian – continued to operate (as they do to this day), and undoubtedly benefited from the lack of alcohol to be had in the centre of the town, as did the pubs in neighbouring Hitchin and Baldock.
New inns also sprang up on the borders of the town, one such example being the Wilbury Hotel which was just outside the town's border.
The Spirella Building, completed in 1920, blends in despite its central position through being disguised as a large country house, complete with towers and a ballroom.
During the Second World War, the factory was also involved in producing parachutes and decoding machinery.
Upon building the new ICL building the remains of a large Roman camp was found, many articles being found and saved for display in the Letchworth Museum & Art Gallery.
In the Second World War, a number of early computers were built in what became known as the ICL 1.1 plant.
According to the book the term "Garden City" derived from the image of a city being situated within a belt of open countryside (which would contribute significantly to food production for the population), and not, as is commonly cited, to a principle that every house in the city should have a garden.