The first buildings of the University of Chicago campus, which make up what is now known as the Main Quadrangles, were part of a "master plan" conceived by two University of Chicago trustees and plotted by Chicago architect Henry Ives Cobb. The Main Quadrangles consist of six quadrangles, each surrounded by buildings, bordering one larger quadrangle. The buildings of the Main Quadrangles were designed by Cobb, Shepley, Rutan and Coolidge, Holabird & Roche, and other architectural firms in a mixture of the Victorian Gothic and Collegiate Gothic styles, patterned on the colleges of the University of Oxford. (Mitchell Tower, for example, is modeled after Oxford's Magdalen Tower, and the university Commons, Hutchinson Hall, replicates Christ Church Hall.)