Lake Baikal is the world's oldest lake, at 25 million years (possibly older), and deepest, averaging 744.4 metres (2,442 ft).

Located in the south of the Russian region of Siberia, between Irkutsk Oblast to the northwest and the Buryat Republic to the southeast, it is the most voluminous freshwater lake in the world, containing roughly 20% of the world's unfrozen surface fresh water.

A South Korean woman looks out at the flood water after a torrential rain storm hit the capital city on July 27, 2011 in Seoul, South Korea. South Korea issued a national crisis warning on as torrential rain caused flooding in parts of the country, killing over 35 with at least ten missing. (Photo by Chung Sung-Jun/Getty Images)

Ryo Minemizu, one of Japan’s emerging stars in the field of marine life photography and the 2017 winner of the Nikkei National Geographic photography prize, captures the beauty and complexity of plankton that drift in our planet’s oceans and other bodies of water in meticulous detail. Here: Batesian mimicry by a Soleichthys fish larva. (Photo by Ryo Minemizu/The Guardian)

“Eye of a toad”. Animal Portraits, Łukasz Bożycki, Poland. Early spring sees a pond near Łukasz’s home city of Warsaw, Poland, full of mating frogs and a few toads. On this March day, Łukasz shared the pond with them for an evening, sitting in the icy water in his chest-high waders, keeping as still as possible, despite the numbing cold, so that the amphibians could get used to him. “I wanted to find a fresh way of portraying the amphibians”, he says, “at water level”. Using a telephoto lens, he focused on one lone toad and waited for the sun to dip almost below the horizon before pressing the shutter, using flash to bring out the details in the shadow. His prize was “the glorious pool of sunset colour” and fiery glow of the toad’s eye. Nikon D80 + 70-300mm f4.5-5.6 lens + extension tube; 1/125 sec at f9 (-2.3 e/v); ISO 100; built-in flash. (Photo by Łukasz Bożycki)

A woman poses on the flooded St. Mark's square during an acqua-alta (high-water) alert in Venice, on November 19, 2013. (Photo by Andrea Pattaro/AFP Photo)

P.S. All pictures, as usual, are presented in high resolution. To see Hi-Res images – just TWICE click on any picture. In other words, click small picture – opens the BIG picture. Click BIG picture – opens VERY BIG picture (if available; this principle works anywhere on the site AvaxNews).

Jacob's Well is a perennial karstic spring in the Texas Hill Country flowing from the bed of Cypress Creek, located northwest of Wimberley, Texas. The twelve foot (four meter) diameter mouth of the spring serves as a popular swimming spot for the local land owners whose properties adjoin Cypress Creek. From the opening in the creek bed, Jacob's Well cave descends vertically for about thirty feet (ten meters), then continues downward at an angle through a series of silted chambers separated by narrow restrictions, finally reaching a depth of one hundred and twenty feet (forty meters). Until the modern era, the Trinity Aquifer-fed natural artesian spring gushed water from the mouth of the cave, with a measured flow in 1924 of one hundred and seventy gallons per second (six hundred and forty liters per second) discharging six feet (two meters) into the air. The spring is the greatest source of water recharging the Edwards Aquifer.

Breitling Wingwalker Freya Paterson, from Liverpool, UK, flies above Kuwait City's iconic Water Towers with pilots David Barrell and Martyn Carrington, on March 6, 2014. The team loop and roll up to 160 mph enduring G-forces of 4-5g. Crowds are expected to line the Kuwaiti coastline to catch a glimpse of the Wingwalking team on Saturday, March 8, 2014, to mark the opening of the first dedicated boutique in the city for the prestigious watch brand. (Photo by Katsuhiko Tokunaga/Breitling)