Children, some in tears, are escorted down a road in Barcelona, Spain, Thursday, August 17, 2017. Police in Barcelona say a white van has mounted a sidewalk, struck several people in the city's Las Ramblas district. (Photo by Manu Fernandez/AP Photo)

is a concentrated solar power plant with a molten salt heat storage system. It is located within the city limits of Fuentes de Andalucía in the province of Seville, Spain.

A man looks at waves as they crash against a lighthouse in the northern Spanish village of Viavelez, Spain January 13, 2017. (Photo by Eloy Alonso/Reuters)

People walk next to of the pantheon of the Marquesa de San Juan de Nieva, chosen as the best tomb sculpture of Spain in a Spanish magazine this week, in the municipal cemetery of La Carriona in Aviles, northern Spain, October 29, 2015. Catholics will mark All Saints' Day on Sunday by visiting cemeteries and graves of deceased relatives and friends. (Photo by Eloy Alonso/Reuters)

Billy Robinson, from Galax, Va., rides Gentleman Jim during the Professional Bull Riders Buck Off, in New York's Madison Square Garden, Saturday, January 17, 2015. The top 35 bull riders compete during the PBR event, returning to New York for the ninth consecutive year. (Photo by Richard Drew/AP Photo)

People watch a competitor riding a homemade vehicle without an engine on a 300-metre-track during the Red Bull Soapbox Race in Amman, Jordan September 4, 2015. (Photo by Muhammad Hamed/Reuters)

Spectators in Moscow were treated to the site of humorously designed makeshift aircraft plunging into the Muskova River during the Red Bull Flugtag Moscow 2011 competition. 38 teams took part at the Flugtag – which means “flying day” – a competition in which teams in fancy dress attempt to pilot human-powered, home-made flying machines off a six-meter-high platform into water.

Photo: A makeshift aircraft plummets into the Moskva River during the Red Bull Flugtag Moscow 2011 competition. (Photo by Sergei Karpukhin/Reuters)