A subway worker walks away after a train departed the station in central Pyongyang, North Korea May 7, 2016. (Photo by Damir Sagolj/Reuters)

A migrant boy sits on railway tracks at a train station in Tovarnik, Croatia, September 20, 2015. (Photo by Antonio Bronic/Reuters)

A child attends a training session in a swimming pool on July 10, 2007 in Wuhan of Hubei Province, China. (Photo by China Photos/Getty Images)

A woman dressed up for Halloween travels on a Metro train in São Paulo, Brazil on October 30, 2017. (Photo by Cris Faga/Rex Features/Shutterstock)

This handout picture released by the Gagarin Cosmonauts' Training Centre on October 17, 2023 shows Marina Vasilevskaya (L) flying during a parabolic flight aboard a zero-gravity simulator, a Russian IL-76 MDK aircraft used for cosmonauts' training flights in weightlessness, in Star City outside Moscow. (Photo by Pavel Shvets/Gagarin Cosmonaut Training Center/AFP Photo)

Collided passenger train cars are seen in Taebaek, South Korea, Tuesday, July 22, 2014. Two passenger trains collided head-on in eastern South Korea on Tuesday afternoon, killing one passenger and injuring dozens, fire officials said. (Photo by AFP Photo/Yonhap)

Train attendants take part in a parade training as they visit the national flag guard during a patriotic education event ahead of the 90th anniversary of the founding of the Chinese People's Liberation Army (PLA) in Beijing, China July 25, 2017. (Photo by Reuters/China Stringer Network)

Female Ukrainian cadets, wearing new military uniforms designed specially for women, take part in a training during the "Uniform matters" event organised to present the outfit and test it under military training conditions, on the outskirts of Kyiv on July 12, 2023. (Photo by Sergei Supinsky/AFP Photo)