There's a word to describe moments such as this and I think it’s probably… eek!

The waters of the Thames are rushing 138ft beneath me and a double decker bus on the road below resembles a scale model.

The pedestrians milling about on the pavements look as if they have come to life from a Lowry painting and there is nothing between them and my boots but a sheet of glass.

It sounds like a scene from Hitchcock’s Vertigo – but it’s the latest attraction at Tower Bridge. And yesterday I joined hundreds of pioneers to look down on London through a glass walkway on the upper part of the bridge.

Read more..http://www.dailymail.co.uk/travel/travel_news/article-2828423/Must-head-heights-London-s-Tower-Bridge-unveils-1m-glass-walkway-dizzying-views-140ft-River-Thames.html