No Follows, Value and Google Bot

Hi Guys,

I am a relative newbie to the world of SEO but I feel I have a pretty good grasp of the basics. However there is one question that bugs me. On sites that have all no-follow links going from them, where does google bot go?

I understand that the webcrawler hops from page to page, following links, indexing data, finding spam etc. However, when it reaches a dead end, a site that has a page full of no-follows (like a BBC news page for example), where does it go? Does it go back on itself or does it use the no follow links to get to another site?

I know its not the most exciting post around but its something that is bugging me. Kinda like there is an answer in front of me but I just can see it...

Thanks for your help