Military vehicles surround a wreckage of a trolleybus, in Volgograd, Russia, Monday, December 30, 2013. A bomb blast tore through a trolleybus in the city of Volgograd on Monday morning, killing at least 10 people a day after a suicide bombing that killed at least 17 at the city's main railway station. Volgograd is about 650 kilometers (400 miles) northeast of Sochi, where the Olympics are to be held. (Photo by Denis Tyrin/AP Photo)

A boy poses with a butterfly on his face during a photocall to promote the “Sensational Butterflies” exhibition at the Natural History Museum in central London, on March 25, 2013. With around 400 live tropical butterflies and moths living in the temporary facility, visitors will get the chance to see them flying freely as well as looking for emerging butterflies at the hatchery window. Running from March 29 to September 15, 2013, the exhibition is housed in a structure in the museum grounds. (Photo by Leon Neal/AFP Photo)

This cable ropeway suspended between cliffs is the only access to Yushan village in Hubei Province, Chin, which has a population of just over 200 people. The ropeway was built in 1997; before that villagers faced a walk of several days to get to the next nearest village. The ropeway, which is powered by a diesel engine, is 1,000 metres long and 400 metres above the valley floor.

The Dynasphere, an electrically-driven wheel, invented by Mr. J. A. Purves of Taunton and his son. It had 2.5 horse power and once attained a speed of 25 mph. (Photo by Fox Photos/Getty Images). 1932

An aircraft crosses a bridge over a highway the airport in Frankfurt, Germany, Friday, September 20, 2019. Protests of the “Friday For Futurte” movement against the increase of carbon dioxide emissions are planned Friday in cities around the globe. In the United States more than 800 events were planned Friday, while in Germany more than 400 rallies are expected. (Photo by Michael Probst/AP Photo)

An Indonesian woman watches an eruption from the Mount Sinabung volcano from Tiga Pancur village, in Karo in North Sumatra on November 3, 2017. Sinabung roared back to life in 2010 for the first time in 400 years. After another period of inactivity it erupted once more in 2013, and has remained highly active since. (Photo by Ivan Damanik/AFP Photo)