My high school class just had a reunion for the first time in years and which I helped organize. The most important thing was picking the venue. Once you choose the right venue with the right food and atmosphere (and reasonable pricing), we are on for a great reunion.
On a warm Saturday afternoon in November, my friend and I went to check out this little bistro we had booked (yes, booked before we tried it as we were running out of time) for our reunion in Hiroo in the same neighborhood where we went to school. It turned out to be a gem.