Katla from a distance. (Photo: Gary J. Wood/CC BY-SA 2.0)

Iceland is home to some 130 volcanoes, with over a dozen considered to be active, and with a few them liable to erupt at any minute. Now, after a tremor and some earthquakes, authorities are saying that one of the country’s biggest, called Katla and located in southern Iceland, could also be close to erupting.

In recent days, according to the Iceland Review, seismic activity has been detected in the mountain, an augur of a potential eruption. The volcano last erupted in 1918, though similar seismic activity was detected in 1977, when it failed to blow its top. 

Yet, Katla is overdue for an eruption, having generally blown once every 50 years since Iceland was first settled in the 10th century. Volcanic activity at the mountain is getting worryingly behind time. 

“There will be an eruption, it’s just a question of when,” Kristín Jónsdóttir, a coordinator at the country’s meteorological service told Icelandic radio Monday, according to the Iceland Review. 

The seismic activity tracked by authorities includes, on Monday, a 3.3-magnitude tremor and, previously, two small earthquakes, both under 5.0 magnitude.

If an eruption begins, Icelanders will have about a few hours’ warning, Jónsdóttir said, as magma works its way from underneath a glacier to the volcano’s top: some time, then, to hunker down and get ready for the show.