In the Art Institute of Chicago hangs one of the most enduring portraits of American nightlife rendered in this century, an icon of urban anomie so widely recognized it has become a cliché for marketing spoofs. Yet hundreds of thousands of visitors who every year come to view the original of Edward Hopper’s "Nighthawks" are struck by its power to rivet our attention on three customers who share a space but nothing else in the stark light of a 1940s diner.

Former poet laureate Mark Strand, now on the faculty at the University of Chicago, has suggested that the power of Hopper’s painting derives from a tension between the geometry of the scene, which seems to compel the viewer on a journey toward an unimaginable place outside the painting—its trapezoid lines leading to a vanishing point someplace in the dark—and the inviting light of the diner, which bids us to stay.

"The diner is an island of light distracting whoever might be walking by—in this case, ourselves—from journey’s end," Strand has written. "This distraction might be construed as salvation. For a vanishing point is not just where converging lines meet, it is also where we cease to be, the end of our individual journeys."

"Nighthawks" hangs in the same room with that other national icon, Grant Wood’s "American Gothic," invoking the republic’s pastoral heritage. It is fitting, perhaps, that in the city where east and west, farm and metropolis, have historically met, the two works should be housed together in one of the world’s proudest museums.

Located at the intersection of Michigan Avenue and Adams Street (111 South Michigan Avenue) on the eastern edge of Chicago’s famous downtown "Loop," the Art Institute houses more than 300,000 works within its 10 curatorial departments. Among its treasures are "A Sunday Afternoon on La Grand Jatte—1884" by Georges Seurat, the painting that inspired and is brought to life in Stephen Sondheim’s award-winning musical "Sunday in the Park with George." Other revered works in the Institute’s collection include El Greco’s "The Assumption of the Virgin," and several of Marc Chagall’s stained-glass windows.

So varied is the museum’s collection that anyone is bound to have his or her favorite room or work of art. But surely one of the Institute’s calling cards is its treasure trove of French Impressionist paintings, which includes the largest group of works by Claude Monet outside of France.

The collection of European paintings includes 950 works from the Middle Ages to 1900. Especially noteworthy are such late 19th century masterpieces as Vincent van Gogh’s "Self-Portrait," Paul Cézanne’s "The Basket of Apples," and Paul Gauguin’s "Ancestors of Tehemana."

The museum’s collection of 20th century painting and sculpture is also considered one of the finest and most comprehensive in the world, with more than 1,500 works representing every significant art movement in Europe and America. Among this collection are legendary works by Pablo Picasso, Henri Matisse, Georgia O’Keefe, Jackson Pollock, David Hockney, Frank Stella, and Andy Warhol. Other striking collections include the Thorne Miniature Rooms, European Decorative Arts 1600-1900, Arms and Armor, Indian and South East Asian art, and Ancient Egyptian, Greek, Etruscan, and Roman art.

Special exhibitions on display when APA members visit Chicago in May include "Monet to Moore: The Millennium Gift of Sara Lee Corporation," "Bilbao: The Transformation of a City," "Appliqued, Embroidered, and Pieced Bedcoverings," and "Maineri to Miro: The Regenstein Collection Since 1975."

One unusual and fascinating exhibit, though many might hesitate to label it a work of art, is the original Trading Room of the old Chicago Stock Exchange, which was saved when the exchange’s headquarters was demolished in 1972 and then reconstructed at the Art Institute.

Museum hours are 10:30 a.m. to 4:30 p.m. Monday, Wednesday, Thursday, and Friday; 10:30 a.m. to 8 p.m. on Tuesday; 10 a.m. to 5 p.m. on Saturday, and noon to 5 p.m. on Sunday. Admission is free on Tuesdays; at other times it is $8 for adults and $5 for students, children, and seniors over age 55. Children aged 5 and younger are admitted free at all times.