Skyscrapers were invented in the US in the 1870s in major cities like Chicago and New York using structural iron and steel instead of masonry. Builders faced challenges with safety standards, wind resistance, ventilation, and transportation within the tall buildings. By the late 19th century, skyscrapers were understood to be steel-framed structures, and between 1902-1931 New York engaged in competition to build the world's tallest building, though the size and height of skyscrapers was controversial due to issues like lack of sunlight and increased density. Rapid urbanization and immigration in the late 19th/early 20th century resulted in widespread slum conditions in major US cities, as tenement housing with poor sanitation became over

1. Urbanization

2. Skyscrapers
 Skyscrapers were invented in the US during
the 1870s in Chicago and New York
 The building materials are structural iron
and steel, instead of masonry
 Builders had to face high risks such as:
demanding standards for safety, wind sheer,
ventilation, and internal transportation.
 By the end of the century, skyscrapers were
understood to be steel buildings

3.  Between 1902 and 1931, New York was
in a competition to build the highest
structure in the world.
 The size and height were controversial
issues
 Downsides to the skyscrapers:
concentrated people into certain
locations, weakened the sense of the
neighborhood, no sunlight,
transportation becomes difficult, and
city becomes crowded and impersonal

4. Slums
urbanization and immigration
gave newcomers very little
options about living space
Slums were everywhere in each
major city in the US
People would crowd into
tenements, apartment buildings
that had few comforts

5. By 1900 slums became a
common occurrence in the
United States
One to two family houses were
subdivided to fit up to 32 families
in one living space
Because of the unsanitary
conditions diseases and reduced
life expectancy was common in
Urban Life