People travel by tube on the London Underground to take part in the Pride in London parade, London, Saturday, July 1, 2023. (Photo by Jordan Pettitt/PA Wire via AP Photo)

An injured young woman is led away after an incident at Parsons Green underground tube station in west London on September 15, 2017. Police and ambulance services said they were responding to an “incident” at Parsons Green underground station in west London on Friday, following media reports of an explosion. A Metro. co. uk reporter at the scene was quoted by the paper as saying that a white container exploded on the train and passengers had suffered facial burns. (Photo by Luke MacGregor/Reuters)

Londoners sleep on the platform and on the train tracks at Aldwych Underground station,London, during heavy all night Nazi bombing raids, October 8, 1940. (Photo by AP Photo)

The Lotus Exhibition Center is an icon for the city of Wujin. Conceived as an addition to an existing underground building with a lake top, the center is a sculptural and ethereal lotus flower displaying the three stages of the lotus bloom life.

Tami Varma, right, and her brother Robin, the grandchildren of Devendra Varma, a scholar of English gothic tales and an expert in vampire lore, pose in coffins at the Bran Castle, in Bran, Romania, Monday, October 31, 2016. A Canadian brother and sister are passing Halloween night curled up in red velvet coffins in the Transylvanian castle that inspired the Dracula legend, the first time in 70 years anyone has spent the night in the gothic fortress, after they bested 88,000 people who entered a competition hosted by Airbnb to get the chance to dine and sleep at the castle in Romania. A portrait of medieval prince Vlad the Impaler is placed on the wall. (Photo by Vadim Ghirda/AP Photo)

Beneath the Swedish capital lies an intricate web of underground train lines. More than 90 of the 100 stations in the 110km tunnel system, sometimes referred to as “the world’s longest art gallery”, have been decorated with paintings, installations, mosaics and sculptures by 150 artists since the 1950s. After spending a couple of weeks exploring arctic Norway and Sweden, London-based travel photographer Conor MacNeill headed underground to capture images of the metro stations. Here: A rainbow arcs over a girl on the platform of Stadion station. (Photo by Conor MacNeill/The Observer)

Participants take part in the 14th annual “No Trousers Tube Ride” event on the London Underground on January 12, 2025. The event, staged by Improv Everywhere, takes place every January in New York City and has since expanded internationally. What began as a small prank with just seven participants has grown into a global celebration of silliness, with dozens of cities, including London, joining in each year. (Photo by Guy Bell/Alamy Live News)

A man reacts to being warned by a British Transport Police officer for not wearing a face mask at King's Cross underground station, London, England on October 8, 2020. (Photo by Jonathan Brady/PA Images via Getty Images)