A business in Gwynedd is offering what could be the world's deepest sleep - a hotel 1,375ft underground only accessible by hike, zip lines and flooded chambers.

Deep Sleep is located in a disused Victorian slate mine below Snowdonia.

Guests can stay in log cabins or slate-roofed chambers - dubbed 'the deepest sleep in the world'.

The unique underground hotel sees people venture down through an abandoned Victorian slate mine to reach the remote off-grid camp.

It has an all-year-round temperature of 10C and the camp comprises of four private twin-bed cabins and a 'romantic grotto' with a double bed.

Visitors at Go Below must traverse an underground route through a series of mines and caverns before reaching Deep Sleep 1,375ft below Snowdonia. Release date September 11 2024. A unique underground hotel experience 1,375ft below Snowdonia's depths promises 'the deepest sleep in the world'. The adventure, promised to be an 'experience like no other on Earth', sees people venture down through an abandoned Victorian slate mine to reach a remote off-grid camp of Deep Sleep. Set a staggering 1,375 vertical feet below the mountains of Snowdonia and with an all-year-round temperature 10 degrees Celsius, the camp comprises of four private twin-bed cabins and a 'romantic grotto' with a double bed.
Visitors at Go Below must traverse an underground route through a series of mines and caverns before reaching Deep Sleep 1,375ft below Snowdonia. Photo: Go Below / SWNS (Go Below / SWNS)

But the adventure begins with a one-hour hike - involving zip lines, steep and vertical terrain and flooded chambers.

Visitors first meet their trip leader at 5pm at their Tanygrisiau Base, near Blaenau Ffestiniog.

From there, they begin a 45-minute walk up into the mountains, which the team admit is 'steep at times, but remote and very beautiful at the top!'

After kitting up with headtorches, helmets, a harness and Wellington boots - adventures must bid farewell to the outside world.

The journey on foot to the mine entrance and through the mine to the Deep Sleep involves two hours or more of walking, 'scrambling ducking and balancing'.

After the treacherous route underground, through ancient miners stairways, 'decaying bridges' and 'scrambles to negotiate', guests reach their loggings and are provided with a warm drink, an 'expedition-style meal' and information on their surroundings.

The price is £375 for a cabin, which takes two people, or £575 for the Grotto (which also takes two people) - which includes an evening meal, breakfast in the morning, and hot/cold drinks.

Visitors at Go Below must traverse an underground route through a series of mines and caverns before reaching Deep Sleep 1,375ft below Snowdonia. Release date September 11 2024. A unique underground hotel experience 1,375ft below Snowdonia's depths promises 'the deepest sleep in the world'. The adventure, promised to be an 'experience like no other on Earth', sees people venture down through an abandoned Victorian slate mine to reach a remote off-grid camp of Deep Sleep. Set a staggering 1,375 vertical feet below the mountains of Snowdonia and with an all-year-round temperature 10 degrees Celsius, the camp comprises of four private twin-bed cabins and a 'romantic grotto' with a double bed.
Visitors at Go Below must traverse an underground route through a series of mines and caverns before reaching Deep Sleep 1,375ft below Snowdonia. Photo: Go Below / SWNS (COPYRIGHT: See previous)

Children aged 14 and over are welcome to accompany adults to Deep Sleep and warm clothes are recommended.

All electric lighting - including the wi-fi in Deep Sleep is low-voltage and powered from 12v batteries.

According to the Go Below team, these batteries are “charged by the force of falling water within the mine itself using micro-hydro turbines”.

They added: "There is no grid connection, so Deep Sleep is self-powered using the mines own natural water courses.

"A Euro V compliant diesel generator on the surface provides backup power to charge the batteries, if there hasn't been much rain lately."

Running water from taps that come from a spring within the mine itself provides “excellent quality” rehydration.

For more information, visit: https://www.go-below.co.uk/Deep-Sleep.asp

Twin-bed cabins 1,375ft below Snowdonia at Go Below Deep Sleep. Release date September 11 2024. A unique underground hotel experience 1,375ft below Snowdonia's depths promises 'the deepest sleep in the world'. The adventure, promised to be an 'experience like no other on Earth', sees people venture down through an abandoned Victorian slate mine to reach a remote off-grid camp of Deep Sleep. Set a staggering 1,375 vertical feet below the mountains of Snowdonia and with an all-year-round temperature 10 degrees Celsius, the camp comprises of four private twin-bed cabins and a 'romantic grotto' with a double bed.
Twin-bed cabins 1,375ft below Snowdonia at Go Below Deep Sleep. Photo: Go Below / SWNS (COPYRIGHT: See previous)