Competitors make their way up Heartbreak Hill during the 2022 City to Surf on August 14, 2022 in Sydney, Australia. (Photo by Jenny Evans/Getty Images)

Family members pose for photos near lava flowing from Pacaya Volcano near El Patrocinio village in San Vicente Pacaya, Guatemala, Friday, April 16, 2021. (Photo by Moises Castillo/AP Photo)

A Syrian Kurdish ballet dancer performs in an empty market during a lockdown to curb the spread of the Covid-19 coronavirus in Syria's northeastern city of Qamishli on April 7, 2021. (Photo by Delil Souleiman/AFP Photo)

Figure skating couple Madison Chock and Evan Bates, of the USA, practice their dance routine during a training session at the 2022 Winter Olympics, Thursday, February 3, 2022, in Beijing. (Photo by Natacha Pisarenko/AP Photo)

The owner of the zoo Pierre Thivillon laughs next to a chimpanzee on May 17, 2021, at the zoological park of Saint-Martin-la-Plaine, two days ahead of its reopening as part of France's latest step toward the ending of its third nationwide Covid-19 lockdown. (Photo by Jean-Philippe Ksiazek/AFP Photo)

Ukraine's Maryna Bekh-Romanchuk reacts during the women's triple jump final at the World Athletics Indoor Championships in Belgrade, Serbia on March 20, 2022. (Photo by Bernadett Szabo/Reuters)

In this picture taken with a drone a man and a woman enjoy the beautiful weather at the Langwieder See (Lake Langwieder) in Munich, Germany, Thursday, June 18, 2020. (Photo by Sven Hoppe/dpa via AP Photo)

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.