West Berliners crowd in front of the Berlin Wall as they watch East German border guards demolish a section of the wall on November 11, 1989. (Photo by Gerard Malie/AFP Photo)

Riders of the Peloton approach a cobbled section near the Arenberg forrest at the 117th Paris-Roubaix cycle race in Wallers, France on April 12, 2019. (Photo by Christophe Petit-Tesson/EPA)

Penitentes, or nieves penitentes (Spanish for “penitent-shaped snows”), are a snow formation found at high altitudes. They take the form of tall thin blades of hardened snow or ice, closely spaced with the blades oriented towards the general direction of the sun.

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.

“This Way Up”. Photographic section portfolio, first prize. A Chinook CH-47 weapon systems operator prepares his aircraft during a training exercise in June 2018. (Photo bu SAC Ed Wright/RAF)

Mary McHugh mourns her slain fiance Sgt. James Regan at “Section 60” of the Arlington National Cemetery May 27, 2007. Regan, a US Army Ranger, was killed by an IED explosion in Iraq. (Photo by John Moore/Getty Images)

A group of colorful row houses are reflected on to the top of a black car parked on 3600 block of N street in the Georgetown section of Washington DC, February 16, 2017. (Photo by John McDonnell/The Washington Post)

A man walks next to a section of the wall separating Mexico and the United States, on the outskirts of Ciudad Juarez, Mexico, November 12, 2016. (Photo by Jose Luis Gonzalez/Reuters)