organizations reside in college-owned housing. Roanoke's original fraternity row, constructed in the 1960s, no longer houses the college's fraternities; the buildings have been converted into residence halls. The Greek organizations are now housed in two locations on the Roanoke campus. Kappa Alpha Order, Pi Kappa Alpha, Pi Lambda Phi and Sigma Chi have houses on the Elizabeth Campus. Alpha Sigma Alpha, Chi Omega, Delta Gamma and Pi Kappa Phi occupy Chesapeake Hall, a residence hall on the main campus; each organization has a floor in the four-story building. Student participation Roanoke's Greek organizations have a prominent role on campus, but are not dominant; approximately 25% of the Roanoke student body participates in Greek life. Roanoke has over 100 student organizations that provide many extracurricular opportunities other than Greek life. Campus Quadrangles Roanoke's main campus is relatively self-contained with most academic buildings and residence halls built around three quadrangles: the John R. Turbyfill Front Quad, the Back Quad (central campus), and the Athletic Quad, which surrounds the college's newest athletic facilities and residence halls. The campus is lined with brick sidewalks and has been recognized for its landscaping and views of the surrounding mountains. The largest Rock Elm in the United States is located near the library. The only Alice Aycock sculpture in Virginia is on the Back Quad. Architecture The campus architecture is a blend of traditional collegiate and modern styles. The Administration Building, constructed in 1848 with bricks made on-site, and six other buildings, Miller Hall, Trout Hall, Bittle Hall, Monterey House, West Hall, and the Old Salem Post Office are listed on the National Register of Historic Places. Two of these buildings, the Administration Building and Monterey House, were built by the Deyerle brothers, Joseph and Benjamin Deyerle. The designers of some of the other historic buildings are unknown, but may have also included members of the Deyerle family. Fintel Library, Colket Student Center, and most residence halls have the traditional style of the older structures. Other newer buildings are more modern; these include Antrim Chapel, the science complex comprising Trexler Hall, Massengill Auditorium, and the Life Science Building, the fine arts building named F. W. Olin Hall, and C. Homer Bast Physical Education and Recreational Center. National Register of Historic Places Seven college buildings are listed on the National Register of Historic Places. The buildings, with year of construction, are: The Administration Building (1848) Miller Hall (1857)