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)

In this Monday, October 8, 2018 photo, Colombia's BMX freestyle athlete Sebastian Martinez practices at the Urban Park, at the Youth Olympic Games in Buenos Aires, Argentina. (Photo by Ian Walton/OIS/IOC via AP Photo)

Christian Bale poses for a fan at the 25th annual Screen Actors Guild Awards at the Shrine Auditorium & Expo Hall on Sunday, January 27, 2019, in Los Angeles. (Photo by Mario Anzuoni/Reuters)

A devotee carrying an idol of the Hindu god Ganesh, the deity of prosperity, jumps into the Sabarmati river to immerse the idol during the 10-day-long Ganesh Chaturthi festival in Ahmedabad, India, September 11, 2016. (Photo by Amit Dave/Reuters)

A spectator cools herself at a water spraying fan at the Australian Open tennis championships in Melbourne, Australia, Tuesday, January 17, 2017. (Photo by Kin Cheung/AP Photo)

Peacocks are seen covered in bags as a protection of their plume during transportation, in Xiangyang, Hubei province, China April 12, 2017. (Photo by Reuters/Stringer)

In this April 20, 2017 photo, a woman is aided by fellow demonstrators after falling, overcome by tear gas, during anti-government protests in Caracas, Venezuela. Tens of thousands of protesters asking for the resignation of President Nicolas Maduro flooded the streets again, one day after three people were killed and hundreds arrested in the biggest anti-government demonstrations in years. (Photo by Ariana Cubillos/AP Photo)

A Palestinian man rides his horse on a beach in Gaza City February 17, 2017. (Photo by Mohammed Salem/Reuters)