In many parts of the Catalan Countries, the local holiday of each town/city (called festes patronals or festa major depending on the area) start at noon with this loud explosion of firecrackers called traca or mascletada. People gather around the square to watch the firecrackers and cheer when they finish, because it means the beginning of the celebrations!
It's difficult to show what it's like on the internet, because a video doesn't do it justice. The point of these firecrackers is to be loud, you can feel them in your body.
Some cities of the Valencian Country are very proud of their big mascletaes. In this video, you can see one of them in the Valencian city of Alacant. It must have felt like an earthquake!
Video by A Punt.










