Stockholm Sightseeing offers a number of tours both by land and by boat. I took their "Under the Bridges" waterway tour and I can recommend it because the only way to really see Stockholm, an area comprise of islands and waterways, is by boat.
The tour I was on was basically in English, the American type of English, which the tour guide spoke so perfectly one wouldn't even know she wasn't a native of America with the possible exception of the fact that her spoken English was in fact better than that of most Americans. The boat was low immaculate clean and comfortable glass covered boat with heat which heat was invaluable as it was off season and rather cold.
The tour took about 2 hours, and true to the tours name, Under the Bridges, took us under all sorts of bridges. Everything along the way was explained and I was able to see sights and obtain views that would have been impossible by land. read more