Architecture tour, Chicago, daytime, sunny, blue sky, Willis Tower (Sears Tower), reflective glass windows, modern skyscraper, steel structure, urban landscape, busy streets, tourists walking, cameras in hand, guide holding umbrella, City Hall building, historic landmark, stone walls, ornate decorations, Wrigley Building, Tribune Tower, gothic style, intricate stonework, Lake Michigan shoreline, sailboats on the lake, city skyline, 3/4 composition, wide-angle lens, vibrant colors, high-contrast lighting.