[12][13] Colloquially referred to as "Cathy" by Pitt students,[14][15] the Cathedral of Learning is a steel-frame structure overlaid with Indiana limestone and contains more than 2,000 rooms and windows.

The building contains noted examples of stained glass, stone, wood, and iron work and is often used by the university in photographs, postcards, and other advertisements.

The fourth floor, which was previously home to the main stacks of the university's library and the McCarl Center for Nontraditional Student Success,[18] now houses a mix of interdisciplinary studies programs.

[22][23][24] Other departments in the Cathedral include English, Religious Studies, Theatre Arts, and the School of Social Work which maintains the highest classrooms in the building located on the 23rd floor.

At that time, the school consisted of a series of buildings constructed along Henry Hornbostel's plan for the campus and included "temporary" wooden structures built during World War I.

It was to make visible something of the spirit that was in the hearts of pioneers as, long ago, they sat in their log cabins and thought by candlelight of the great city that would sometime spread out beyond their three rivers and that even they were starting to build.Bowman looked at a 14-acre (5.7 ha) plot of land named Frick Acres.

The design took two years to finish, with the final plan attempting to fuse the idea of a modern skyscraper with the tradition and ideals of Gothic architecture.

Local legend states that to counteract this resistance, Bowman ordered that the construction of the walls would start at the top floor and work its way down, so the project could not be canceled.

This has been traced to an account on November 21, 1943, issue of At Ease, a tabloid related to local military personnel on campus, which stated that "the masonry was started from the top downward."

On July 26, 1940, as World War II was starting, a bomb threat was made against the structure with extra guards being posted to secure it and the authorities not ruling out possible wartime sabotage.

The main part of the cathedral's first floor, the Commons Room, called one of the "great architectural fantasies of the twentieth century", is a fifteenth-century English perpendicular Gothic-style hall that covers half an acre (2,000 m2) and extends upward four stories, reaching 52 feet (16 m) tall.

The wrought iron in the room, including the large gates leading to the elevators, was a gift from George Hubbard Clapp and was designed by the ironworker Samuel Yellin.

Each nationality room is designed to celebrate a different culture that had an influence on Pittsburgh's growth, depicting an era prior to (or in the singular case of the French Classroom, just after) 1787, the year of the university's founding and of the signing of the U.S. Constitution.

Funded by a Babcock family grant of $327,000 ($3.45 million in 2023 dollars[52]) and dedicated in November 1958,[44] all of the room's features are original, except for the lighting, furniture and carpeting.

The walls, featuring intricate geometric patterns, are paneled in Appalachian white oak with burled walnut inlays and touches of rosewood.

Mrs. A. E. Braun donated the furnishings and floral carved mahogany wood paneling which she had purchased in 1941 from the library of the home of Grant McCargo in the East End of Pittsburgh.

[59] Other features of the room include a low bookcase, bordered and topped with classic carving, that was crafted by university carpenters to replace the original fireplace whose inclusion was impractical on the 12th floor, along with two crystal drop chandeliers.

The rooms were originally part of William Croghan Jr.'s mansion, known as the Picnic House, built in 1830 in the Stanton Heights area of Pittsburgh.

The rooms themselves were created in 1835 by the Philadelphia carver Mordecai Van Horn, and they have been regarded as being among the most lavish examples of Greek Revival designs in America.

[38] His daughter, Mary Elizabeth, went to boarding school in New York, but in 1842 at the age of fifteen she eloped with 43-year-old Edward Wyndham Harrington Schenley, a captain in the British military.

William S. Miller, then president of Steelwood Corp., purchased the Croghan mansion following World War II and it was soon leveled for a new housing development, but the Croghan-Schenley rooms were spared.

A centerpiece element in the room is a Nicholas Lochoff reproduction of The Resurrection by Piero della Francesca that was purchased for the lecture hall by Helen Clay Frick.

[69] The University of Pittsburgh's Humanities Center, part of School of Arts and Sciences, is housed in the Cathedral of Learning's room 602, which was a sixth-floor space once occupied by the Darlington Memorial Library.

The library collection is particularly rich in material about the French and Indian War and the history of Western Pennsylvania and the Ohio Valley, as both William and Mary Darlington researched and published in these areas.

[82] Made possible by a gift from F. James and Foster J.J. McCarl,[82] it was designed by Alan J. Cuteri and his architectural firm Strada, LLC, and includes wood finishes, double-height spaces with high ceilings and windows, a main corridor conceived as an interior street, and many elements that refer to the Cathedral of Learning's Gothic architecture including decorative painted metal columns with contemporary buttress-style arches.

Also hanging in a hallway on the fourth floor outside the space, three unsigned and undated 7-by-3-foot (2.1 by 0.9 m) glass-encased murals that depict Renaissance painting styles and which have long belonged to the university but are of unknown origin.

[84] The room features wood floors, fluted ionic columns, red velvet draperies, and student chairs with leather seats.

[88] In 2017 the Studio Theatre was named in honor of Pitt alumnus Richard E. Raugh who donated $1 million to support it and the university's theater productions.

The Frederick Honors College provides support and enriched opportunities for scholarship among the university's undergraduates and offers a Bachelor of Philosophy (BPhil) degree.

[90] The 2002-2003 renovation, by Rothschild Doyno Collaborative of Pittsburgh's Strip District, showcased an existing two-story arched window that is visible at night for miles around.