Saturday 24. Juni 2017 in Tübingen http://www.tuebix.org/
We'll have a Debian booth at this year's Tübix  event and continue last year's activities: we'll try to set up a Debian package mirror/cache. We can offer help installing stretch if there are people interested in the by then brand new release.
Everybody is welcome to help and join the booth, bring stickers, posters, ...and further ideas.