The early hours of a Sunday morning might normally be disturbed by the sound of late-night revellers or early morning dog-walkers.
But for seven members of the Rotary Club of Hitchin Tilehouse, their charity sleep-out in Hitchin Market Place was interrupted by something altogether more supersonic.
The hardy team of charity fundraisers pitched their tent in Hitchin Market Place on Saturday night, sleeping overnight in the square to raise funds and awareness for local homeless charities and ShelterBox - a Rotary charity which provides international assistance to families surviving winter in some of the world's harshest places.
At about 4.20am on Sunday morning - just when most of the team were finally bedding in for the night - the RAF sonic boom reverberated across Hertfordshire, with one of the bleary-eyed team commenting in the morning: "The RAF fly-past was much appreciated!"
On an otherwise peaceful sleep-out, the Hitchin Tilehouse team set up camp in the square following the Christmas lights switch-on, and served hot soup to passersby - while also on hand with bacon rolls on Sunday morning.
Organiser and former Tilehouse president David McIntosh said that keeping warm was "one of the biggest challenges for the team," but thankfully overnight temperatures didn't fall as low as they had feared.
"There was a lot of interest from those passing by about our local homeless charities and ShetlerBox," David said.
"Many thanks to the people of Hitchin - their generosity was astounding. One kind person donated as they passed early on Sunday morning, only to return an hour later with all their saved change."
In total, nearly £1,000 was raised for the Rotary Club's respective charities.
Bob Harris, president elect of the Rotary Club of Hitchin Tilehouse, said: "The event was Tilehouse at our best. We were surprised by just how vibrant Hitchin Town Centre is in the small hours of Sunday morning - but the real surprise was the sonic boom.
"Officially, it was the RAF intercepting a suspicious aircraft, but I'd like to think they were performing a fly-past for us, either way it was loud!"
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