A volcano continues to erupt in southwestern Iceland, prompting evacuations of the nearby town of Grindavik. It’s the fourth time it has gone off in four months.

The eruption “opened a fissure in the earth about 3 kilometers (almost 2 miles) long between Stóra-Skógfell and Hagafell mountains on the Reykjanes Peninsula,” The Associated Press reported.

Hundreds of residents and tourists were also evacuated from the popular Blue Lagoon geothermal spa due to the eruption. It hasn’t affected flights at nearby Keflavik Airport as of yet, per The New York Times.

What we know about the Iceland volcano

The volcano system first started spewing red-hot lava in December. Tectonic plates spreading away from each other underneath the island nation are responsible for the volcanic activity.

Will it erupt again? The last time there was volcanic activity in this region of Iceland was 1200. The volcanic system has been brewing below the surface all that time, and “experts say it could be active for decades or centuries to come,” according to The Washington Post.