How to keep a classic hotel dining room from resting on its laurels? Heed the history, update the spirit. Among the recently revamped, go to:

New Orleans: The Pontchartrain Bistro and Wine Bar, Pontchartrain Hotel, 2031 St. Charles Ave.; (504) 524-0581

When the Garden District’s Pontchartrain undertook a renovation of its eatery, construction crews uncovered the hotel’s original 1927 terrazzo floors, Venetian glass windows, and hand-painted wood-beamed ceiling, all concealed since 1941. Though it still offers the hotel’s signature Mile-High Pie, the eatery’s reformed French-New Orleans menu caps the restoration of everyday cafe into scenic boîte.

Rome: Vivendo, St. Regis Grand Rome, Via Vittorio Emanuele Orlando 3; 011-39-06-47091

Famed hotelier Cesar Ritz himself founded Rome’s Grand Hotel as the continent’s grandest in 1894. A century-plus and some $40 million later, the St. Regis group
restored the Grand’s good name last year. Now its just-opened restaurant, Vivendo, breathes modern life into handsome antique quarters with daring Asian-Italian
fusion food and, keeping the old stuff where it counts, a 350-vintage wine list.

New York: ONEc.p.s., Plaza Hotel, Fifth Ave. at Central Park South; (212) 583-1111

Designer Adam Tihany swept the cobwebs from the Plaza’s dated Edwardian Room, keeping its good 1907 bones — mahogany inlaid ceiling, mosaic floors, and wood paneling — while adding a dash of trendy decor via banquettes and lighter colors. From caviar and scrambled eggs at breakfast to steak frites for dinner, American brasserie fare completes the culinary rebuild. —