Welcome to WebmasterWorld Guest from 188.8.131.52
there is one other alternative, of course... and that is to just allow google to index the whole lot, even though they are old. it might even bring in a bit of extra traffic.
I use living URLs from year to year, so after a recurring event expires, it disappears from all active navigation and taxonomy pages of the site, and a notice appears on the event page that the event has expired and we're awaiting the next update. But I do not noindex it. This is also what I do with recurring events where, say, this year's was cancelled.
"...the pages all have proper content on them, they are not thin -- they are just out of date (the date of the event will still be shown on the page)."
[edited by: Robert_Charlton at 9:14 am (utc) on Aug 26, 2013]
Here's a discussion we had in mid-2011
i think i'm going to try taking all the "noindex" off, and allow google to index the whole lot.
if no one can point to any penalties (other than the normal thin content and duplicate content ones, which i'm confident don't apply), then what is the harm in allowing google to index them?