While Petrodvorets was trashed by the Germans in WWII (what you see today is largely a reconstruction), according to recent historians it suffered heaviest damage under Soviet bombing raids in December 1941 and January 1942. This was because Stalin was determined to stop Hitler from his plan of hosting a New Year's victory celebration inside the palace.
While a visit here is highly recommended, if you plan to see all the various museums in the estate it can also be an expensive and frustrating affair. The total cost for entering the lower park and all the palaces and museums is R1900. Plus many of the museums have different closing days, and some are closed or only open for weekends from October to May.
The Upper Park is free - the gardens here are lovely. Admission to the Lower Park is payable at the cash booths on the jetty and outside the gates leading to the Grand Cascade; hold on to your ticket when exiting this area so you can go back in later if you need to.
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