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.

Toddlers by Karolina Bazydlo. (Photo by Karolina Bazydlo; Source: Flickr)

“I See Sea” by Photographer Dmytriy Dokunov. The frozen Black Sea. Scene of action: Odessa, Ukraine; January, 2012. (Photo by Dmytriy Dokunov)

The car of Dan Wheldon of England driver of the #77 Bowers & Wilkins Sam Schmidt Motorsports Dallara Honda (left) flies in the air during the Las Vegas Indy 300 part of the IZOD IndyCar World Championships presented by Honda on October 16, 2011 at the Las Vegas Motor Speedway in Las Vegas, Nevada. (Photo by Robert Laberge/Getty Images)

Rihanna arrives for the Stella McCartney Special Presentation at 13 North Audley Street during London Fashion Week Autumn/Winter 2012 on February 18, 2012 in London, England. (Photo by Samir Hussein/Getty Images)

1. Jennifer Lopez