Mountain biking, or Velo Tout Terrain/VTT if you're of the French persuasion, promises to be as big as skiing one day. Tourist authorities and ski lift companies have long since recognised the potential, and now the Chamonix Valley is one of the great mountain bike areas to head for once the snows have receded.
Easier (flatter!) trails can be found on the floor of the valley with a number of easier / family mountain bike routes located between Argentière and Chamonix.
If down (but not up) is your thing, make best use of the many bike friendly chairlifts in the Chamonix valley, which can be used to access a number of breath-taking downhill trails.
Or, for the more adventurous, try heading for the high cols and enjoy some exhilarating Alpine trails.
Bike friendly accommodation
You'll soon notice the difference.