By scraping the results of each tour stage in the history of the Tour de France (from 1903 to 2019) from Wikipedia, we were able to answer these questions in a poster (approx. 40 × 60 cm).
Each wheel represents an edition of the Tour de France. The thickness of the rim (white) shows the average speed of the winner of that year: a narrower rim is faster. The spokes in the wheels are the stages of the Tour, and more space between two spokes means that a longer stage has been ridden.
The same has been done for the Giro d’Italia and the Vuelta a España.
We made this poster for Studio Vlak.