Hot air balloons fly over Igualada during an early flight as part of the European Balloon Festival on July 10, 2014 in Igualada, Spain. The early morning flight of over 30 balloons was shorter than expected due to windy weather. This flight is organised as a curtain raiser for the four-day European Balloon Festival. Now is the 18th year of the most important hot air Balloon event in Spain and one of the biggest in Europe. (Photo by David Ramos/Getty Images)

Stacked stones are pictured during the European Stone Stacking Championships 2018 in Dunbar, Scotland, on April 22, 2018. The European Stone Stacking Championships are Europe’s largest championships for all Stone Stacking and Rock Balancing artists and practitioners. The overall winner of the European Stone Stacking Championship will receive financial support for flights to the World Stone Balance Championship in Llano, Texas the following year. (Photo by Andy Buchanan/AFP Photo)

GDT Naturfotograf 2014 – “Die besten Naturfotografien des Jahres”. Radomir Jakubowski – Spieglein Spieglein. 2nd place: Mammals. (Photo by Radomir Jakubowski)

A competitor solves a Rubik's cube using his feet as he prepares for the Rubik's Cube European Championship in Prague, Czech Republic, July 15, 2016. (Photo by David W. Cerny/Reuters)

Roman Amoyan of Armenia, bottom, and Elman Mukhtarov of Azerbaijan compete in the the Men's wrestling, 59kg Greco-Roman Bronze Medal event at the 2015 European Games in Baku, Azerbaijan, Saturday, June 13, 2015. (AP Photo/Dmitry Lovetsky)

Amateur contestants (L-R) Phil Bailey, John Hindle and Eren Emir pose in telephone booths during the annual European Elvis Tribute Artist Contest and Convention in Birmingham, central England January 2, 2015. (Photo by Darren Staples/Reuters)

The land-robot “teleMAX” of German company telerob stands next to soldiers during a trial at the German army base on May 18, 2010 in Hammelburg, Germany. ELROB provides an overview of the current state of affairs in European unmanned system technology and to evaluate commercial off-the-shelf products for military use. It is to show what is feasible in robotics, to support technological developments in Europe, and to find solutions for the current military challenges. (Photo by Ralph Orlowski/Getty Images)