and Birmingham that were growing rapidly, and the first suburban districts sprung up around downtowns to accommodate those who wanted to escape the squalid conditions of the industrial towns. Initially, such growth came along rail lines in the form of ribbon developments, as suburban residents could commute via train to downtown for work. In Australia, where Melbourne would soon become the second-largest city in the British Empire, the distinctively Australasian suburb, with its loosely aggregated quarter-acre sections, developed in the 1850s and eventually became a component of the Australian Dream. Toward the end of the century, with the development of public transit systems such as the underground railways, trams and buses, it became possible for the majority of a city's population to reside outside the city and to commute into the center for work. By the mid-19th century, the first major suburban areas were springing up around London as the city (then the largest in the world) became more overcrowded and unsanitary. A major catalyst for suburban growth was the opening of the Metropolitan Railway in the 1860s. The line later joined the capital's financial heart in the City to what were to become the suburbs of Middlesex. The line reached Harrow in 1880. Unlike other railway companies, which were required to dispose of surplus land, London's Met was allowed to retain such land that it believed was necessary for future railway use. Initially, the surplus land was managed by the Land Committee, and, from the 1880s, the land was developed and sold to domestic buyers in places like Willesden Park Estate, Cecil Park, near Pinner and at Wembley Park. In 1912 it was suggested that a specially formed company should take over from the Surplus Lands Committee and develop suburban estates near the railway. However, World War I (1914–1918) delayed these plans until 1919, when, with the expectation of a postwar housing-boom, Metropolitan Railway Country Estates Limited (MRCE) formed. MRCE went on to develop estates at Kingsbury Garden Village near Neasden, Wembley Park, Cecil Park and Grange Estate at Pinner and the Cedars Estate at Rickmansworth and to found places such as Harrow Garden Village. The Met's marketing department coined the term Metro-land in 1915 when the Guide to the Extension Line became the Metro-land guide, priced at 1d. This promoted the land served by the Met for the walker, visitor and later the house-hunter. Published annually until 1932