Thanks Maxim, That's pretty obvious I suppose - providing that a root at Server context level is always the default in absence of root in Location Block. I had only been reading the docs for 30 mins, after downloading nginx, and that just jumped out at me. I'd better make sure I read all the docs before posting here again - but I still think "Pitfalls" could be more specific, moanby chrisrob - Nginx Mailing List - English
Practically the first two pages I read when starting with nginx were: http://wiki.nginx.org/Pitfalls which says "putting Root inside Location Block is BAD" - don't do it. and http://nginx.org/en/docs/beginners_guide.html which gives this as its example of a config file: The resulting configuration of the server block should look like this: server { location / {by chrisrob - Nginx Mailing List - English