Just off the lakeside square dedicated to the statue of Emperor Lý Thái Tổ stands a worn-out monument colloquially known as the Frog Garden Fountain. It's a rectangular stone pillar standing on a pool decorated with sculptures of frogs and dragons, unassuming but somewhat whimsical.

It appears to be of no particular note at a glance, but it hides a little secret from the French Colonial era.

Installed in 1901, the fountain is the oldest surviving one in the city. It is the centerpiece of the surrounding Diên Hồng Flower Garden, a popular spot for a daily leisure walk and wedding photography. Almost unchanged since its inauguration, the old fountain is a bit dilapidated but remains functional, even for its original purpose: being a tomb.

Housed in the upper part of the pillar are the remains of Léon Jean Laurent Chavassieux, the governor-general of Indochina from 1894 to 1895. The garden itself was created in commemoration of him, and it was originally named after the colonists until Mayor Tran Van Lai renamed it Diên Hồng in 1945.