Tallinn is wonderful! In addition to the perfectly-preserved Medieval town, there is a fascinating layer of background on the former Soviet occupation that will likely be of interest to many, if your guide can include some of that. Plan to spend extra free time there—you'll want to. Great for dining, exploring and souvenirs.
Out tour had an unfortunate and odd extension where we left the old town and boarded a local commuter train to visit a local suburb. Our guide did her best to present this as worthwhile, but it was a short rail trip to a short walk through some slightly tired, indistinct local streets (no particular points of interest) and finished in a nice, but "anywhere" farmer's market. It was a waste of time, pretty much.
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