The British Geological Survey (BGS) received almost 200 reports from an automatic online questionnaire survey from members of the public who had felt it just after 7.35pm on Thursday.
Almost all of them came from within a 12.5 mile radius of the epicentre which was just over six miles to the west of Fort William and two miles south of Loch Eil. Responses came from the relatively more densely populated areas of Fort William, Spean Bridge, Kinlochleven, Ballachullish and the villages on the eastern shore of Loch Lihnne.
Further afield, reports were received from the Loch Nevis area, Acharacle, Lochaline on the Sound of Mull and the island of Lismore. It was even felt just south of Oban, almost 40 miles away.
The BGS said there were many reports of windows rattling. One resident said there was a "one second loud rumble followed by sound like thunder and crockery on Welsh dresser rattled".
Some said it sounded like an explosion and several reported their houses shaking. One report said: "Vibration on floor with audible rumble which got progressively louder", another said "the floor shook so much and you could hear the house rattle and an shake around us" and a further one said "it felt like a big explosion underneath the property which seemed to lift and drop it".
Julian Bukits, assistant seismologist at the BGS, said "At 2.9 on the scale it was average in the UK and insignificant in global terms. The most significant earthquake in the UK registered 5.4 in 1984 on the Lleyn Peninsula in North Wales."
Fort William and Ardnamurchan councillor Andrew Baxter was among those who felt the tremors.
He said: "I was sitting in a community council meeting in Nether Lochaber when we heard a low grumbling rumble. We weren't sure whether it was a large lorry going past or a clap of thunder. But I think everyone came to the conclusion, once had a quick look outside, that it was an earth tremor.
"I wouldn't say it was frightening, more confusing, just trying to work what it was. But I was in quite a rickety old village hall and it certainly shook that for the few seconds it lasted."