Swiss police officers stand beside of mock gates of the NEAT Gotthard Base Tunnel inside the event hall for the upcoming opening ceremony near the town of Erstfeld, Switzerland May 31, 2016. The celebrations of the opening of the Gotthard Base Tunnel will start on June 1, 2016. With a length of 57 km (35 miles) crossing the Alps, the Gotthard Base tunnel is the world's longest train tunnel. (Photo by Arnd Wiegmann/Reuters)

Femen activists with their bare chests reading “Fascists out of ballot boxes” are held back by Catalan regional police forces Mossos d'Esquadra as they protest against far-right Vox party candidates in Barcelona during regional elections in Catalonia on February 14, 2021. Catalonia is voting in an election overshadowed by the pandemic which Madrid hopes will unseat the region's ruling separatists more than three years after a failed bid to break away from Spain. (Photo by Lluis Gene/AFP Photo/Profimedia)

An Afghan man works at a traditional yarn factory in Heart province, Afghanistan July 28, 2015. (Photo by Mohammad Shoib/Reuters)

Sikh Nihang (Sikh warriors) perform “Gatka”, an ancient form of Sikh martial arts, during the “Nagar Kirtan” procession to mark the 339th birth anniversary of the Sikh warrior Shaheed Baba Deep Singh, in Amritsar on January 31, 2021. (Photo by Narinder Nanu/AFP Photo/Profimedia)

Joe Deedon, president of TAC ONE Consulting, demonstrates searching for a shooter in a middle school during an Active Shooter Response course offered by TAC ONE in Denver April 2, 2016. According to TAC ONE, the course, which is offered for the first time to concealed weapons permit carrying civilians, is designed at preparing people to effectively save lives prior to the arrival of law enforcement at an active shooter incident. (Photo by Rick Wilking/Reuters)

A reveller takes part in the battle of “Enfarinats”, a flour fight in celebration of the Els Enfarinats festival on December 28, 2015 in Ibi, Spain. Citizens of Ibi annually celebrate the festival with a battle using flour, eggs and firecrackers. (Photo by Pablo Blazquez Dominguez/Getty Images)

The Jade Belt Bridge, also known as the Camel's Back Bridge, is an 18th-century pedestrian Moon bridge located on the grounds of the Summer Palace in Beijing, China. It is famous for its distinctive tall thin single arch.

The RNLI Swanage lifeboat in Dorset, UK churns the water as it performs some manoeuvres on September 13, 2025. (Photo by Lewis Johnstone/BNPS)