During the 19th century, London was transformed into the largest city in the world with its unprecedented population growth from about 580 thousand in 1700 to 1 million in 1800 . Even with this rapid growth, the urban form in London rarely changed. Area of the city began to expanded after the late 18th century. The city with extremely high population density made the urban environment narrow, dirty and dangerous. Increasing social inequity led slums to be swarmed around industrial sites and outskirt of the city (Figure 2).
