A few weekends ago I took part in the Arc`teryx Chamonix experience. I signed up for Introduction to Glacier safety and hiking on day one. I did not realize at the time that I was going to have to climb down a succession of rather long ladders (250m worth to be exact) that are bolted to a shear rock face. 

You must also move from one ladder to the next on a rocky lip that is not as wide as a boot, or barely. There are rails to clip to as you move along to the next ladder. Going down I seemed quite fine, even though being a past sufferer of vertigo. I did belay the first two ladders but then felt fine and went the rest of way ropeless. On our return, after a day on the glacier and trying out various techniques for scaling ice walls above a glacial river, we had to ascend these ladders. This is when my mind went a little wobbly.