Travel concept: commercial airplane flying with beautiful charming stewardess on September 12, 2019. (Photo by Volodymyr Tverdokhlib/Alamy Stock Photo)
A tourist walks inside the Ice Palace glacier hollow at Hintertux glacier, located at around 3250 meters above sea level, in Zillertal, Austria, 02 March, 2016. The hollow's temperature remains constant at 0 degrees Celsius, in summer and winter alike, and is also used by the University of Innsbruck for scientific research projects. (Photo by Lisi Niesner/EPA)