San Francisco 's Civic Center is a blend of glorious beaux arts architecture and striking modern design. The recently restored City Hall, at Polk and Grove streets, is the visual center. Built in 1915 and modeled after St. Peter's Basilica in Rome , this stunning gilded dome of sandstone and copper reaches more than seven inches higher than the nation's Capitol in Washington , D.C. Around the corner on Van Ness Avenue is the War Memorial Opera House, designed by Arthur Brown, Jr., the same architect who designed City Hall. Flanking its right side is the ultra-modern, glass-and-granite Louise M. Davies Symphony Hall. Just east of City Hall on Larkin Street is the striking Main Library, with its five-story, skylit atrium, marvelous local history wing and revolving exhibits. Tours are offered Wed. and Fri., at 2:30 p.m. Map 2, B7