Are the tours essential to a good day here or will the audio tour and gardens suffice for a visit of say 4 hours?
Not essential. The audio guide is very good, and there are guides around if you have questions.
We only used the audio as were limited for time but I suspect the guided tour would be worthwhile. We only walked through the formal gardens as it was too cold and far to venture further
I think the tours added to the overall experience of the day. It wasn’t necessary to take the tours and the self guided auto tour is excellent but if you are only going to make one visit then I’d recommend them and 4 hours is plenty of time. They take you to the places the self guided tour doesn’t. The tours take about 50 minutes each and the self guided tour about an hour which leaves time for a walk round the gardens. I visited for 4 hours and although only went around the gardens closest to the palace managed to have lunch.
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