The gate to the Garden of Eternal Spring at the Old Summer Palace, historically an entrance for the emperor only, has opened to the public for the first time after renovation, Beijing Times reported.

The Old Summer Palace, known in Chinese as Yuan Ming Yuan, is an imperial garden built in the Qing Dynasty (1644-1911) that was sacked and destroyed by British and French forces in 1860 during the Second Opium War.

The gate to the Garden of Eternal Spring, one of three gardens at the Old Summer Palace, was also burnt to the ground.

After it was restored, the gate had never been open to the public until Tuesday, the 156th anniversary of the sack and torching of the royal residence.

On the anniversary, memorial activities ranging from an art exhibition to academic lectures were organized to memorialize the past. The previously closed gate was opened to the public for free, which organizers say will become a tradition starting this year.

A senior official said the plank road paving at the Old Summer Palace has been completed, and a total of 86 historical heritages registered.

To date, only about 20 percent of underground relics at the palace have been excavated.