The Roman aqueduct in Segovia, Spain, is pictured at twilight. Dating to the first century A.D., the well-preserved structure is listed as a UNESCO World Heritage site.
Some of nature's intricate patterns are on display in this magnified view of the mineral azurite. The bright blue mineral was once used to make paints and may still be found in jewelry.
Veiled Woman on Doorstep
A veiled Nepali woman, covered head-to-toe in shades of blue, pauses to rest in a colorful doorway in one of the small Himalayan hill towns found in Nepal's Anapurna region.
These distinctive webbed feet belong to a blue-footed booby of the Galápagos Islands. The bluer, the better: Courting males show off with a high-stepping strut—and those with brighter feet are more attractive to potential mates.
Frost covers the brilliant blue leaves of lush ferns in New Zealand's Fiordland National Park. The park is an isolated wilderness that's home to more than 700 plants found nowhere else in the world.
A homey-looking igloo lights up the stark landscape on a cold night in the Canadian Arctic. These temporary shelters were commonly used by indigenous peoples in the frigid North American Arctic.
As startling as a bright-blue eye, a central lagoon peers out from Rocas Baimbridgen in Ecuador's Galápagos Islands. The stark, rocky island teems with life at times—the brackish lagoon waters are favored by flamingos.
Unveiling the regalia that has captivated humans (and hens) for thousands of years, an Indian peacock displays his colorful train at an Australian reserve. Males may use their feathers to attract harems of several hens.
A group of chinstrap penguins lines the edge of an iceberg adrift in Antarctic waters. Chinstraps are among the most abundant penguins, and some colonies live on floating icebergs.
Holidaymakers take the plunge and enjoy a twisting, turning trip down an Israeli waterslide. The attraction cools tourists who visit the shores of the Sea of Galilee.
The sweeping color of sea and sky, blue is a common thread in nature, seen in the cerulean of a whale shark (pictured here), the indigo of a stormy night, and the cobalt of a peacock's feathers. Over the centuries, the hue has come to represent calm, cold, mysticism, and sadness.
A dog jumps into Lake Banyoles in northern Spain. The lake is the country’s second largest.
A one-inch, translucent goby swims above a giant clam in the Pacific Ocean. Goby fish are among the smallest vertebrates in the world.
Leaping Polar Bear
A polar bear leaps off of sea ice near Devon Island in the Canadian Arctic. Strong swimmers, polar bears have slightly webbed paws to aid in paddling.
Colorful stripes merge to give a five-lined skink a striking blue tail. The common lizard ranges throughout the eastern United States.
San Marco Basin
A costumed tourist poses before a view of San Marco Basin in Venice, Italy. For every resident Venetian, hundreds of visitors pour into the city each year.
A bow is drawn across the strings of a colorfully painted violin in Asheville, North Carolina. Nestled in the Blue Ridge Mountains, Asheville is known for its bohemian art and music scenes.