I am currently writing an article:
Migration - BirdForum Opus | BirdForum for our Opus. It is still a work in progress and it still has a long way to go. To that end, if anyone has first hand knowledge of any good migration destination sites or stop-over sites, please add a link where possible, or a name with country and a quick summary to this discussion.
It doesn't have to be long, just a bit about importance and size, if it doesn't have a link, or a mention elsewhere. If it is a great site, or of major international importance, it is probably within a national park or it may be a Ramsar (convention on wetlands), or Convention on the Conservation of Migratory Species (CMS) site. I should be able to find a website if you leave a site name.
Thanks very much for your help.