IUB's 1,931 acres (7.8 km²) includes copious green space and historic buildings dating to the university's reconstruction in
the late nineteenth century. The Works
Progress Administration built much of the campus's core during the Great Depression. Many of the campus's buildings were
built and most of its land acquired during the 1950s and 1960s, when first soldiers attending under the GI Bill and then the Baby Boom swelled the university's
enrollment from 5,403 in 1940 to 30,368 in 1970.The campus rests on a bed of Indiana limestone, specifically
Salem limestone and Harrodsburg limestone,
with outcroppings of St.
Louis limestone. Many of the campus's buildings, especially the older central buildings, are made from Indiana limestone
quarried locally.A stream (and storm sewer) flowing through the center of campus is named for David Starr Jordan, Darwinist, ichthyologist, and president of IU and later Stanford University.