Ride the Wind Day takes place on August 23, 2017. It is the anniversary of the first human powered flight to win the Kremer prize. The Kremer prizes are a series of monetary awards, that are given to pioneers of human-powered flight. The first Kremer prize was won on August 23, 1977 by Dr. Paul MacCready when his Gossamer Condor was the first human-powered aircraft to fly a figure eight around two markers one half mile apart, starting and ending the course at least 10 feet (3.0 m) above the ground.
Wind is the flow of gases on a large scale. On the surface of the Earth, wind consists of the bulk movement of air. Wind figures prominently in several popular sports, including recreational hang gliding, hot air ballooning, kite flying, snowkiting, kite landboarding, kite surfing, paragliding, sailing, and windsurfing. In gliding, wind gradients just above the surface affect the takeoff and landing phases of flight of a glider.
For aerodynamic aircraft which operate relative to the air, winds affect groundspeed, and in the case of lighter-than-air vehicles, wind may play a significant or solitary role in their movement and ground track. (With material from: Wikipedia)