Chamonix is beautiful. We went in the summer one year. Took cable car to top of Aguilla Du Midi. Got stunning pictures of glaciers. It was over 10,000 feet up. Some folk were suffering with altitude sickness, so we swapped our tickets with them, so they could get down again asap. Also did a chairlift ride up another mountain & got left dangling for about 30 minutes. Now hubby & I not too good with heights. It didn't feel too bad though as due to angle, we were only about 15 feet off nearest bit of ground, but it was still pretty far up the mountain. Great views though.