Mecca at Night during Haj, Saudi Arabia

Photograph by Thomas J. Abercrombie

A quarter million Muslims jam Haram Mosque in the holy city of Mecca to pay homage to Allah. Those in the center (blurred in this time exposure) circle the black-draped Kaaba, most sacred of Islamic shrines. Muslims believe the Prophet Abraham—like Muhammad a messenger of God—and his son Ishmael built the first structure here.

New York Skyline

The Top of the Rock, an observation deck atop the Rockefeller Center in New York, offers a front-row view of Manhattan's skyline. The borough is home to a staggering 1.6 million people—12 per 5,000 square feet.

Meteora Monastery, Greece

At one time, there were 24 peak-top monasteries in the region of Meteora in central Greece. Built on sandstone megaliths that rise up to 1,800 feet from the valley floor, the first of these precarious enclaves dates to the 14th century. Now accessible by road and bridge, earlier monks and pilgrims had to rely on ladders and baskets raised by winches to reach the top.