When to Go
To see the palaces and estates at their best, try to time your visits to coincide with spring or summer. Peterhof in particular is best visited in summer, so you can fully appreciate the fountains, statues, monumental cascades, and lush parks. From late September to early June the fountains and cascades are closed down and take on the depressing look of drained pools. Autumn can also be a pleasant time for viewing the palaces. The waterway along the Neva River and Lake Ladoga to Valaam is only open from the end of May through October.
If you're traveling in the extreme cold of winter or the hottest days of summer, dress carefully, as much of your time will probably be spent outdoors.