Who has won the 'King of the Mountains' jersey most times in Tour de France?

Explanation

The French rider Richard Virenque is the rider to have won the polka dot climbing jersey the most times in Tour de France - he has won it 7 times altogether: in 1994, 1995, 1996, 1997, 1999, 2003 and 2004. He played a key role in the so-called 'Festina case' in 1998 and afterwards admitted having been doped.