Initial estimates suggest the quake, which struck just before midnight on Friday, measured between 3.8 and 4.2 magnitude on the Richter scale.
Away from the epicentre, tremors were also felt in Cardiff and Pontypridd, and even as far away as Birmingham. The depth of the earthquake was measured at around 3.5 kilometres by the British Geological Survey.
Shallower earthquakes are felt more strongly because they are closer to the surface.
People were quick to post about it on social media, saying how they heard a loud bumping noise before their houses shook.
Reports described “the whole house was shaking”, “the rumbling and the bang woke me up”, “my bed seemed to move side to side”, and it “was like a large explosion”, the British Geological Survey said.
This is not the first time Wales has experienced an earthquake, although they are rare and are generally relatively weak. Friday night’s quake did not reach record levels, with the strongest tremors in Wales recorded in the 1980s.
The last earthquake of a similar strength to hit the area was in October 1999, according to earthquaketrack.com. On that occasion a magnitude of 4.5 was recorded, with the epicentre about seven miles from Glynneath.
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