An earthquake of magnitude 4.4 struck Britain on Saturday, the British Geological Survey (BGS) said on Saturday, with tremors felt across parts of Wales and southwest England.
The BGS said the epicenter of the quake was 20km north of the Welsh city of Swansea.
Quakes that strong only hit the UK every three to five years, the BGS said on Twitter.
It was the biggest tremor to hit the UK on land since 2008, and the strongest in the southern Wales area since 1906.
In comparison, a 4.4 shake wouldn't even make it into the top 100 quakes to have hit Christchurch in the past decade.
Around 10 million people would have felt the quake, scientists said, but it didn't cause damage.
"Thoughts are with those who have been affected by loss of internet connection/WiFi," police in the south Wales town of Carmarthen joked on Twitter.
Swansea University was temporarily evacuated.
Reuters / Newshub.