The chief challenge in building a bridge across New York's East River was that the depth of the river and the length of the crossing meant that establishing any moorings for the bridge was nearly impossible. The original engineer, John Augustus Roebling, decided to use caissons, watertight retaining structures, which were placed into the East River to allow construction workers to build the bridge. The caissons were so deep that they caused a particular illness known as "caisson disease," a decompression sickness resulting from the pressure inside the caissons.

The Prairie School of Architecture developed in the Midwest in the 1890s as a reaction against the then-popular neo-Classicalism and Beaux-Arts styles. Prairie School Architects sought an authentically American style of architecture that reflected American landscapes. The term, "Prairie School," came about as a comment on the way the broad, plain style of architecture reflected the prairies of the Midwest.

Beaux-arts architecture, named after France's national art school L'Ecole des Beaux-Arts, featured grand structures embellished with baroque details and ornamentation. The Grand Central Terminal in New York was built in 1871 and refurbished in 1913, placing its construction at the height of the Beaux-Arts movement. As such, the railroad station's bronze statuary, ornate grand hall, and finer details make it a key example of the style.

In 1834, the Houses of Parliament burned down in the middle of London, which created the need for a new building to house the government of Great Britain. With rising Victorianism, the commission to build the new House of Parliament went to Charles Barry, who was an early proponent of the Neo-Gothic style. The style hearkened back to the dominant architectural style of the fourteenth to sixteenth centuries, which used grand features such as flying buttresses and ornate windows.

"Beaux-Arts" takes its name from the national art school in France, but describes a separate movement among architects in the United States from roughly 1880 to 1920. The movement was defined by a sweeping neoclassicism that used Baroque motifs, featured a hierarchy of spaces (making grand entryways more important than living areas), added ornate elements like statues and vaultings, and usually employed flat roofs on buildings. The Beaux-Arts style was surpassed by Modernist architecture that valued clean lines and functionality over design details.

Until the late nineteenth century, buildings had serious vertical size restrictions due to the weight placed on them by bricks and other traditional materials. With the introduction of steel, an alloy of iron, new possibilities were available to builders. In particular, the use of steel-frame construction, which built a "sheet" around steel beams, allowed for buildings stretching taller than ten stories.

The Washington Monument, in the center of the National Mall in Washington, D.C., is the world's largest memorial obelisk. Obelisks, four sided pillars that originated with the ancient Egyptians, have long been used in Western culture as memorial markers. The Washington Monument was conceived in the 1840s as more than just the obelisk, but ran into funding problems and was only completed in its simpler form in 1885.

A geodesic dome is a dome that features small triangle shapes over its face, which are created through the intersection of circles throughout what would be the total sphere. These triangles allow for the stress of the building's weight to be distributed over its entire structure, which allowed larger domes to be built in the twentieth century. The innovative architect Buckminster Fuller first demonstrated the architecture was possible, actively sought out opportunities to build domes, and coined the term "geodesic dome."

The Chrysler Building in midtown Manhattan was the tallest building in the world for eleven months, spanning from its completion in May of 1930 to the completion of the Empire State Building. Apart from sheer size, the Chrysler building was also notable as a shining example of Art Deco design. The building's brick artifice, metal crown, and use of modern technological design all were exactly in line with Art Deco's chief features.

"Beaux-Arts Architecture" refers to the style promoted by the École de Beaux-Arts in Paris, but especially as promulgated by Americans who had studied there and produced work in the late nineteenth and early twentieth centuries. The style was a mix of neoclassicism and rococo elements, with the unifying themes being grand spaces, small classical flourishes, flat roofs, arched windows, and fancy embellishments around doors and windows. Any utilitarian spaces were hidden from any obvious views in favor of grand entrances and sweeping hallways.