1 / 4   Hot-air balloons crowded the skies over the Russian village of Dubovoye during an international festival called "Belogorye Sky". /VCG Photo

2 / 4   Hot-air balloons, of all shapes and patterns, attracted a crowd of spectators, with a red heart-shaped aircraft proving to be the crown jewel of the event. /VCG Photo

3 / 4   Hot-air ballooning is an activity that requires excellent skills and a cool head. The destination of a  balloon largely depends on the wind as the pilot can only control the altitude of the balloon, while air currents decide its direction and speed. /VCG Photo

4 / 4   The first hot-air balloon can be traced back to the 17th century. /VCG Photo