James Stewart

Imagine that, underfloor heating while you walk to the shops.

That's my kind of luxury.

But with this growth comes new vulnerabilities.

More people means more infrastructure now sits in places that will be affected by future eruptions.

And by future, I don't mean in hundreds of years.

I mean as soon as tomorrow, because something even more sinister is brewing below the surface.

In late 2019, something changed.

Earthquakes shook the ground beneath Fagradalsfla, an area less than an hour's drive from Reykjavik.

And I'm sorry for my pronunciation here, Icelanders, let me know how I get on.

They started small, but soon multiplied and strengthened.

By early 2021, more than 40,000 earthquakes shook the region in a matter of weeks, in what's known as seismic swarms.

Terrifying, absolutely, but also a geological warning.

Something was going on just a few kilometres below the surface.

Seismic swarms can be caused by magma forcing its way up through cracks in Earth's crust, in what's known as an intrusion.

Rock fractures, magma floods in, pressure builds, and it's often only a matter of time until it reaches the surface.

In March 2021, the ground finally gave way, and a fissure ripped open in Fagradosh Vyakh.

I said I'd come back to this place, and it went on for nearly six months before suddenly stopping.

But that was not a return to dormancy.

That was just the start.

Further eruptions followed in 2022, and again in 2023.