Today, Vietnam is renowned for its stunning landscapes, rich cultural heritage, fast-moving economy, and delicious cuisine. However, to truly understand Vietnamese culture as a traveler, one must dedicate some time to exploring its history.

For the past 30 years, Ms. Thach has been leading tours of the underground tunnels in Vinh Moc, near Hue, Vietnam. “In early 1992, I started taking visitors to the tunnels, and all you could see were the craters from the bombs from the American War,” she remembered as we drove out to see the underground village during a recent trip to Vietnam.