Washington D.C., architectural landmarks tour, daytime, sunny weather, clear blue sky, guided group, mixed ages, casual clothing, walking, historic buildings, columns, arches, domes, Neoclassical styles, marble floors, grand staircases, intricate details, United States Capitol Building, White House, Lincoln Memorial, Washington Monument, National Gallery of Art, Smithsonian Institution, scenic cityscape views, vibrant greenery, blooming flowers, wide-angle lens, panoramic composition, natural lighting.