Clay is used to produce firecrackers. Each clay firecracker weighs between 30kg and 80kg.
The festival involves seven teams, with over 200 firecracker makers from Ninh Giang, Tu Ky, and Gia Loc districts participating.
The key to making firecrackers that produce loud bangs when thrown against the ground is selecting clay free from impurities.
Firecracker makers must be in good health and have experience participating in clay firecracker contests.
Clay firecrackers are a traditional folk game in the northern region, involving hurling clay crackers to create noise.
The game is played to pray for good harvests and no natural disasters in the upcoming year.

It is believed that the louder the noise, the more bountiful the crops will be in the upcoming year.
The festival attracts many locals and tourists.
The event is part of the ongoing Con Son-Kiep Bac 2023 spring festival in Hai Duong province.
A foreigner is excited to explore Vietnamese culture through the spring festival in the northern region.