If you are not able to get tickets to visit the palace, then really this place is not worth going. Basically you are not able to see any impressive buildings, just the main entrance and some walls. Other than that, it is just a glorified garden that is sprawling. No more than a 10-15 minute photo stop. If you are walking from Tokyo station , it is a 15 minute walk. Hence I won't go if there is no palace tour.
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