Dhofar Region, Oman. Much of Oman is desert, but the Arabian Sea coast in the Dhofar region represents a startling difference in climate. This coastal region catches the monsoon rains, or khareef, during the summer months. Drenching rains fall primarily on the mountainous ridge that separates the lush, fertile areas along the coast from the arid interior, recharging streams, waterfalls and springs that provide plentiful water supplies in the fertile lowlands for the remainder of the year. Image taken by Landsat 5 on April 2, 2005. (Photo by USGS/NASA)

Discovered in 1952 by French bio-speleologist Henri Coiffait, the waterfall and accompanying sinkhole were fully mapped in the 1980s by the Spéléo club du Liban. The cave is also known as the "Cave of the Three Bridges." Traveling from Laklouk to Tannourine one passes the village of Balaa, and the "Three Bridges Chasm" (in French "Gouffre des Trois Ponts") is a five-minute journey into the valley below where one sees three natural bridges, rising one above the other and overhanging a chasm descending into Mount Lebanon. During the spring melt, a 90–100-metre (300–330 ft) cascade falls behind the three bridges and then down into the 250-metre (820 ft) chasm. A 1988 fluorescent dye test demonstrated that the water emerged at the spring of Dalleh in Mgharet al-Ghaouaghir.

Night lovers; Hormozgan province, Iran. “In this picture, you can see the Milky Way rising on a fascinating spring night on the Persian Gulf coast. The stunning cliffs of this area make every viewer imagine and even talk to them! The light pollution from a faraway city was quite strong, so it was a challenging post-processing process. I’m a nightscaper who tries to achieve an artistic look in my images, and in this image, I tried to convey and capture the magic of this location”. (Photo by Mohammad Hayati/Milky Way Photographer of the Year)

A Romanian female soldier adjusts her helmet before taking part in weapons training with US Marines female counterparts at the Capu Midia Surface to Air Firing Range, on the Black Sea coast in Romania, Monday, March 20, 2017. About 1,200 US and Romanian troops take part in the Spring Storm 17 exercise, meant to simulate defense of the Romanian Black Sea coastline and urban areas. (Photo by Vadim Ghirda/AP Photo)

A Chinese woman wears a mask to protect from particles blown in during a sandstorm as she walks in the street on May 4, 2017 in Beijing, China. Sandstorms are common in northern China during the spring season and are caused when heavy winds from Mongolia in the north brings sand and pollutants that can blanket Chinese cities and cause air quality to deteriorate. (Photo by Kevin Frayer/Getty Images)

People canoe through a flooded forest in Soomaa national park, Estonia, February 7, 2016. In this Estonian region hit by floods every spring the natural disaster is used to attract visitors and organise canoe tours through flooded territories. The floods are called Fifth Season by local people. (Photo by Ints Kalnins/Reuters)

Workers put some finishing touches on “Forever Marilyn”, a sculpture by Seward Johnson, on July 14, 2011 in Chicago, Illinois. The stainless steel and aluminum sculpture which stands 26 feet tall and weighs 34,000 pounds will be unveiled tomorrow and remain on display in Chicago through the spring of 2012. The sculpture was inspired by Marilyn Monroe's iconic scene in the 1955 movie “Seven Year Itch”. (Photo by Scott Olson/Getty Images)