World's Greatest Swimming Pools: Four Seasons, Serengeti Pool, Tanzania. A show of elephants, buffalo and baboons awaits thanks to an active watering hole below the free-form infinity pool at this plush hideaway inside Serengeti National Park. Bonus: Because of infrared technology at the hole, guests can be notified on their bedroom TV when animals are approaching. When you've got word of wildlife on the horizon, catch them from your private terrace – or head back to the pool. (From $1,650). (Photo by Four Seasons)

Queen Elizabeth II (as Princess Elizabeth) writing at her desk in Windsor Castle, Berkshire. (Photo by Lisa Sheridan/Studio Lisa/Getty Images). 30th May 1944

Britain's Queen Elizabeth boards a train at Kings Cross station in London, in this December 17, 2009 file photo. Queen Elizabeth celebrates her 90th birthday on April 21, 2016. (Photo by Stefan Rousseau/Reuters)

Lisa Snowdon (C) takes part in the launch of the new Veet Easywax campaign in a bid to find “Britain's Greatest Legs” on February 23, 2012 in London, England. (Photo by Tim Whitby/Getty Images)

A scorpion crawls out of the mouth of Thailand's Scorpion Queen and Ripley's Ambassador Kanchana Kaetkaew (also spelled Kanjana Ketkaew), at the Ripley's Believe it or Not museum in Pattaya city, Chonburi province, Thailand, 03 June 2017. (Photo by Diego Azubel/EPA)

Female soldiers of the self-proclaimed Donetsk People's Republic hold flowers backstage during a beauty pageant to mark International Women's Day in Donetsk, March 7, 2015. (Photo by Marko Djurica/Reuters)

Debutantes Amira Rayner, 19 (L) and Eliza Lewis, 17 (R) prepare at Boughton Monchelsea Place ahead of the Queen Charlotte's Ball on September 9, 2017 in Maidstone, England. (Photo by Jack Taylor/Getty Images)

People wrapped in blankets sit on the road as they are evacuated from a hotel after an earthquake in Kumamoto, southern Japan, in this photo taken by Kyodo April 14, 2016. A powerful earthquake with a magnitude of 6.5 knocked over buildings in southern Japan on Thursday evening, and police said people may be trapped underneath. (Photo by Reuters/Kyodo News)