Unlike the chief churches of other European cities, St Anne's Cathedral (often just called Belfast Cathedral) doesn't have a history stretching back far into the Renaissance or Middle Ages. It was begun in 1899 and, although basically finished in the 1980s, still lacks some finishing touches (like a steeple!)
Outside, it's a looming pile of stone, basically neo-Romanesque in style. Inside, it's intricately patterned, with black-and-white marble floors representing the paths of virtue and vice; immense stained glass windows; carvings depicting Belfast life; and a wondrous mosaic, made by two sisters out of countless pieces of colored glass.
St Anne's Cathedral is in the very heart of Belfast, near the University of Ulster and the Castle Court Shopping Center.