Someone had an interesting day 2. I can't believe you had the chance to tour in the Imperial Citadel of Thăng Long. The place is freaking cool with military stuff; it has two bunkers that were used by the N. Vietnam war by their leaders. For me I find this very interesting. Deep underground, with air filtering and doors to withstand a nuclear blast. Reminded me a bit of Offutt Air Force Base, or Churchill’s bunker (albeit much smaller). This's an interesting place to understand Vietnam's Imperial past and in addition have a glimpse within the Vietnam War.
yes, i too enjoy those sort of military sites. There was another one that looked far more creepy but it was marked off unfortunately. I wish i had more time to visit more of them but i only got a few days left!