The popular Blue Lagoon geothermal spa, one of Iceland’s biggest tourist attractions in the country’s southwest, was reopened Sunday after authorities said a nearby volcano had stabilized after erupting four days earlier.

Oddný Arnarsdóttir, the head of Visit Iceland, said authorities had redone the security zones in the area and based on that the lagoon was safe to reopen for tourists. “Blue Lagoon opened again today,” she said.

Hundreds of tourists bathed in the lagoon, with the view of the erupting crater in the background. Cameron and Natalie Pacileo, tourists from North Carolina, said they were delighted to see the volcano from the lagoon.

“It’s pretty wild. It’s a beautiful view, and nice that they reopened so we can experience it,” said Natalie Pacileo.

The eruption Wednesday was the fifth and most powerful since the volcanic system reawakened in December after 800 years, gushing record levels of lava as its fissure grew to 3.5 kilometers (2.1 miles) in length.

The activity last week once again threatened Grindavik, a coastal town of 3,800 people, and led to the evacuation of the geothermal spa.

Grindavik, which is about 50 kilometers (30 miles) southwest of Iceland’s capital, Reykjavik, has been threatened since a swarm of earthquakes in November forced an evacuation in advance of the initial Dec. 18 eruption. A subsequent eruption consumed several buildings.

Iceland, which sits above a volcanic hot spot in the North Atlantic, sees regular eruptions. The most disruptive in recent times was the 2010 eruption of the Eyjafjallajokull volcano, which spewed huge clouds of ash into the atmosphere and led to widespread airspace closures over Europe.