At the dead of night, the photographer – known to his Instagram followers as Dark Cyanide – heads out to look for hidden gems, like abandoned stations, provisions and tunnels. His intriguing images feature vibrant streaks, graffiti, and tight framing – and by adding individuals to some to some of shots, he is also able to depict the incredible scale of some of the tunnels. Here: Unnamed subway track in New York City. (Photo by Dark Cyanide/Caters News)

A rail worker fixing a fog warning notice at South Woodford Railway Station in Essex. (Photo by H. F. Davis/Topical Press Agency/Getty Images). 20th October 1938

A person practices ski-joering at the Avoriaz resort in the French Alps on February 11, 2021. (Photo by Jeff Pachoud/AFP Photo)

A hiker walks in the Zillertal Alps during an autumn day near the village of Ginzling, Austria, October 15, 2019. (Photo by Lisi Niesner/Reuters)

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)

Doesn’t taking a nap in a hammock outdoors sound lovely? Perhaps not when you’re hanging in the air, thousands of feet above ground, between two mountains in the Italian Alps! Which is exactly what these adventurous folks did during the International Highline Meeting in Monte Piana, Italy. (Photo by Sebastian Wahlhuetter Photography)

The buildings of the banking district are seen through thousands of rain drops on a glass railing in central Frankfurt, Germany, Wednesday, January 11, 2017. (Photo by Michael Probst/AP Photo)