While the science geek in me is super thrilled, I'm concered about the possibility of radical groups using this knowledge to their advantage. They now know where to go and how to access certain parts of the collider, thus far only known to a selected few. I'd love to hear the thoughts of others on HN.

This is completely a non-issue.

CERN can be visited by anyone for free, and you can take as many pictures as you want. During long shutdowns you can even visit underground facilities. Plans for every building are publicly available at maps.cern.ch, and there's practically no private information here other than worker's personal data. Google for a couple minutes for .cern.ch websites and see for yourself.

Source: I work at CERN

Belize me, If I was a "radical", I would have found other ways to reach my goals and obtain this information.

So I do not think fearmongering necessary.