VINH LOC DISTRICT, VIETNAM—An ancient quarry that supplied stone to Vietnam’s 600-year-old Ho Dynasty Citadel has been found near the Xuan Dai Mountains. Sixteen stones that had been cut from the mountains and smoothed have been found at the site. “It proves that to build the citadel, the Ho Dynasty raised an enormous amount of human and material resources,” said Nguyen Xuan Toan of the Center for Conservation of the Ho Dynasty Citadel World Heritage Site.