The citadel is in a small town called Vinh Loc. I couldn’t find mention of any tours that go there and there is no direct public transport options for other cities where you might be travelling through. In the end, I found a local bus that took 90 minutes from a city called Thanh Hoa, which I was not intending to visit. It seemed like the easiest way, though, short of hiring a car and driver for a day. I guess I was hoping there might be a good payoff for all this effort.
There wasn’t. Not with the citadel itself, that is. I appreciate that this is a historically-significant site but the only thing that really remains is the large stone wall, about 900 metres long on each side. It’s an impressive wall and so I decide to walk along it. In the centre is where the citadel’s buildings would once have been. However, now there is nothing left.