A Swiss police officer accompanies a migrant from Syria carrying her baby, upon her arrival at the railway station in the north-eastern Swiss town of Buchs September 1, 2015. (Photo by Arnd Wiegmann/Reuters)

Gold bars from the vault of a bank and Swiss one franc coins are seen in this illustration picture taken in Zurich November 20, 2014. The “Save our Swiss gold” proposal, spearheaded by the right-wing Swiss People's Party (SVP), aims to ban the central bank from offloading its reserves and oblige it to hold at least 20 percent of its assets in gold. The referendum is scheduled for November 30. The SVP argues it would secure a stable Swiss franc. (Photo by Arnd Wiegmann/Reuters)

Climbers place a huge 80x80 metres (262x262 feet) Swiss national flag on the western face of the north-eastern Swiss landmark Mount Saentis, Switzerland on July 31, 2018. (Photo by Arnd Wiegmann/Reuters)

The Canton Tower and skyscrapers are illuminated during a rehearsal for the 2023 Guangzhou International Light Festival on November 20, 2023 in Guangzhou, Guangdong Province of China. The 12th Guangzhou International Light Festival will be held from November 21 to 30. (Photo by Wu Wenjun/VCG via Getty Images)

Vatican Swiss Guards stand attention at the St. Damaso courtyard on the occasion of the swearing-in ceremony at the Vatican, Sunday, October 4, 2020. The ceremony is held to commemorate the day in 1527 when 147 Swiss Guards died protecting Pope Clement VII during the Sack of Rome. (Photo by Gregorio Borgia/AP Photo)

A handout picture provided by Solar Impulse on 18 March 2015 shows the Swiss solar-powered plane Solar Impulse 2, HB-SIB, taking off with Swiss explorer Andre Borshberg on board for the third leg Ahmedabad to Varanasi, of the Round-The-World, in Ahmedabad, India, 18 March 2015. Swiss explorers Bertrand Piccard and Andre Borschberg attempt to circumnavigate the world flying with an aircraft, with a 72 metres wingspan, powered only by solar energy without a drop of fuel. (Photo by EPA/Solar Impulse)

Photo taken at the top of the Canton Tower, a landmark in Guangzhou, on August 7, 2022 shows the Pearl River running through downtown of Guangzhou, capital of south China's Guangdong Province. (Photo by Liu Dawei/Xinhua News Agency)

Photochromes are vibrant and nuanced prints hand-coloured from black-and-white negatives. Created using a process pioneered in the 1880s, these images offer a fascinating insight into the world when colour photography was still in its infancy. A Tour of the World in Photochromes is at the Swiss Camera Museum, Vevey, until 21 August. Here: Street food in the Strada del Porto in Naples, Italy, 1899. (Photo by Swiss Camera Museum/The Guardian)