Thursday marks 20 years since the deadly Indian Ocean tsunami. How to pass on the memories of and lessons from the disaster has become a challenge.

The tsunami was triggered by a massive earthquake that struck off the coast of the Indonesian island of Sumatra on December 26, 2004. It caused damage to a vast area spanning from Southeast Asia to East Africa, leaving more than 220,000 people dead or missing.

More than 160,000 people were killed in Indonesia's Aceh province, located near the quake's epicenter. Houses, roads and other infrastructure have been rebuilt there with international assistance.

The population of the province's capital, Banda Aceh, stood at about 260,000 as of 2023, returning to the pre-disaster level.

The number of people who were born or moved there from other places after the tsunami has been increasing. The city now faces the challenge of finding ways to pass down the memories and lessons of the disaster to younger generations.

A memorial ceremony organized by the provincial government is to take place in Banda Aceh on Thursday.

Prayers will also be offered to those who died in other stricken areas, such as Sri Lanka and Thailand.