A description inside the Ngoc Son Template states:

Ho Guam Tortoises are closely attached to the legend the King Le returned the precious sword to the Tortoise Genius of Ho Luc Thuy (the former name of Ho Guom during that period of time) in the 15th century.

Since then the lake has had a new name: Ho Hoan Kiem (Lake Hoan Kiem or Lake of Sword Restored) or Ho Guom for short.

Over the past five centuries, people have still believed that the sacred sword was buried deep somewhere in the lake.

Time and again several tortoises in Ho Guom have turned up with the witness of many Hanoians as well as tourists as if they remind lookers on of the historical pages in the heroic struggles of the Vietnamese people.