The campus was organized as an open quadrangle with Nassau Hall at the center. In the second half of the 19th century, the University entered a period of rapid expansion that saw the evolution of a park-like setting and a more organic and less symmetrical approach to architecture. This period was followed by a major building program in the early 20th century, which included a master plan for growth, one of the first of its kind for a university.
Building on campus slowed with the Great Depression and World War II, picking up again in the early 1960s due largely to increased government spending for laboratory buildings. Many of the new buildings were of contemporary design, departing from the collegiate gothic style across campus.
Today, following a major campus planning initiative launched in 2005, the campus continues to grow to accommodate significant academic expansion while preserving the historic beauty and walkability of the campus.