The quake was described as being like a train rumbling past
An early morning earthquake has shaken homes and set off dogs on fits of "mad barking and growling" in the Highlands.
The British Geological Survey (BSG) said a seismic event of a magnitude of 3.4 was detected at 0428 BST.
It has received reports of it being felt in Fort William, Glenfinnan, Ardgour, Strontian and Drumnadrochit.
Robert Hawkes, who lives in Glenfinnan, told the BBC Scotland news website that a rumbling built to a bang which sounded like a gun being shot.
He said: "I thought our central heating boiler had blown up."
The quake woke him and his wife Carole and was felt by their son Chris, who lives in Fort William.
Mr Hawkes said: "We run a family website design business and were swapping notes about our experiences when we met up with Chris at nine this morning."
On its website, the BGS said it had received a number of reports from residents.
Many of the communities affected lie along the Great Glen fault line.
BGS received descriptions of it sounding like "a train rumbling past" and that "dogs also went mad barking and growling".
The survey said the shaking was described as moderate and lasting for up to three seconds.