We took a day trip from Hoi An to Hue (following the Hai Van Pass) to visit the ancient Citadel and Forbidden City. We weren't disappointed. Although there is a lot of restoration work being done (they need to be careful to restore and not replace) the forbidden city, particularly the inner Purple City) were charming. There weren't many tourists so we invariably had whole sections to ourselves. A few things to watch out for: expensive food sellers within the Forbidden city (take your food and drink with you) and the ticket sellers may have made a mistake (although I somehow doubt it) when they gave me 10,000 Dong change when it should've been 100,000 Dong...when I pulled them up, they handed over the correct change without complaint but I have a feeling this might happen more often than just a once-off.
Also, try to go to the toilet before you get there - the facilities were crude at best.
Take your camera - it's a photographer's delight!
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