Don't rush through this 1913 beaux-arts station hall like Metro North's commuters. Grand Central Terminal evokes the romance of rail travel and it's worth spending at least an hour falling in love with its treasures. Start by strolling across the marble-trimmed concourse to gaze at the vaulted aquamarine ceiling depicting the night sky's constellations. The starry wonder isn’t original – it’s a 1944 copy covering water damage in the first fresco designed by French painter Paul Cesar Helleu. A 1990s renovation added twinkling lights (part of Helleu's plan) and cleaned the ceiling. Follow Cancer's claws to the northwest corner to a tiny black rectangle: an original patch of soot, approximately nine-by-five inches, caused by decades of air pollutants. While admiring the work, examine the layout. The zodiac is actually backwards. After its unveiling, railroad officials swatted away critics,