Ho Citadel is located in my home town. It is not easy to go there if you are not a local person. Infact,every day, there are some car which take people from Ha Noi to Ho Citadel and Ho Citadel to Ha Noi. It is very cheap. It is only 5$ for one person. If you come to Ha noi and you like going to Ho Citadel but you don't have a car, I can help you (show and may pick you up to the car). My email is: phamhoa9.9.1978@gmail.com