Urban photographer Roman Robroek spent five years scouring the continent for the grandest examples of forgotten architectural beauty. Here: Watch your step on this Polish spiral staircase. (Photo by Roman Robroek/South West News Service)

A knight parades in the street during the traditional carnival parade in Cologne, western Germany, Monday, February 16, 2015. (Photo by Martin Meissner/AP Photo)

Breitling Wingwalker Freya Paterson, from Liverpool, UK, flies above Kuwait City's iconic Water Towers with pilots David Barrell and Martyn Carrington, on March 6, 2014. The team loop and roll up to 160 mph enduring G-forces of 4-5g. Crowds are expected to line the Kuwaiti coastline to catch a glimpse of the Wingwalking team on Saturday, March 8, 2014, to mark the opening of the first dedicated boutique in the city for the prestigious watch brand. (Photo by Katsuhiko Tokunaga/Breitling)

Supporters of presidential candidate Gustavo Petro, with the Historical Pact coalition, celebrate after his candidate won a presidential runoff in Bogota, Colombia, Sunday, June 19, 2022. (Photo by Fernando Vergara/AP Photo)

Indian Naga Sadhus, or naked holy men, participate in a procession before taking a “shahi snans”, or holy bath, at the Sangam river, the confluence of three of the holiest rivers in Hindu mythology, the Ganga, the Yamuna and the Saraswati, during Kumbh Mela festival in Allahabad, Uttar Pradesh, India, 15 January 2019. The Hindu festival is one of the biggest in India and will be held from 15 January to 04 March 2019 in Allahabad. (Photo by Rajat Gupta/EPA/EFE)

On Dale A. Browne’s first trip to Yellowstone, he “got the best shot” he’d ever taken after chasing this weasel for 30 minutes. The trip for the 58-year-old from Manassas, Va., was a gift from his wife and an opportunity to improve his photography skills with the help of guide and professional photographer Tom Murphy. (Murphy did not assist in the taking of this photo). (Photo by Dale A. Browne)

A man carries food supplies on a donkey to Dhalamlam Mountain in the Jafariya district of the western province of Raymah, Yemen June 2, 2016. In villages perched high on a mountain in Western Yemen, residents are a safe distance from a conflict raging throughout most of the country but have had to turn the clock back on their lifestyles by centuries. (Photo by Abduljabbar Zeyad/Reuters)

A blurred panaroma of Roemerberg historic center is reflected in a soap bubble in Frankfurt am Main, Germany, 09 July 2015. (Photo by Frank Rumpenhorst/EPA)