The quake of 4.4 magnitude has sent ripples across the country after starting in Swanse, Wales at 2.31pm today - Saturday, February 17.
The quake happened just after 2.30pm on Saturday.
Videos on social media showed people gathered outside Swansea University, which was holding an open day, after an apparent evacuation.
The British Geological Survey said the epicentre was near Cwmllynfell in Swansea Valley and at a depth of 7.4km. However, no reports of serious damage or injury has been recorded.
Britain's biggest quake in ten years has reportedly been felt from Cornwall to Liverpool.
A spokesman for the BGS said: "It was a reasonably-sized natural disaster".
On average, the United Kingdom typically experiences one similar-sized natural disaster every 2-8 years.
"I was sat writing in the loft when the table, computer and whole floor shook for a couple of seconds".
But not everyone felt the earth move, with others complaining they had missed it.