Pho Hien is a historic citadel located in Hung Yen, Vietnam. It was once a bustling trading port during the 16th and 17th centuries, attracting merchants from all over Asia. Today, visitors can explore the ancient streets, visit the old houses, and learn about the rich history of this important trading hub. The citadel is also home to several temples and pagodas, offering a glimpse into the spiritual side of Hung Yen. Don't forget to try the local delicacies at the nearby food stalls, where you can savor traditional Vietnamese dishes.