This is a great example of where you can create multiple drop down menus with something as simple as layers using show and hide functions.
Every menu on this navigation bar has been produced using these functions and since doing it I have realised it could be even simpler.
By positioning the hide layer in such a way that it forms a rectangle around the complete menu, you can use one closer to close out all the displayed menus. (Tried this and it doesn’t work, so forget that suggestion, you will need separate closers)
A really neat way to produce drop down or pop up menus that are truly search engine friendly. Review my earlier post on this topic that describes how to create drop down menus using layers. This will give you the basics and the Euro Traveler UK site will show you whats possible with this method, and as I said this can be further improved and simplified as well. I might just do that when I have a little time spare.