cities were the product of industrialization, initially wealthy lived in the city center and the further you went, the poorer things got, trolly cars and new industrialization reversed this, prior to electric trolley, horses pulled them, very slow and produced tons of manure each day, transportation had to improve in order to meet the demands of urban sprawl, growing congestion and increasing value of land pushed architects to search for ways to make buildings taller\=mass production of steel, this led to the first skyscraper to be built in Chicago in 1885 (10 stories), elevators followed (allowed cities to grow upward instead of outward), the promise of money (jobs) drew people into the cities), they also wanted to experience a vibrant urban culture, entertainment, electricity, schools, stores, restaurants, museums, art galleries, etc.