Underground Adventure in Snowdonia: Climbing, Abseil & Zipline

The only lights are your headtorch and the rock around you.

Underground Adventure in Snowdonia is a five-hour activity exploring an abandoned slate mine with optional climbing, abseil, short zipline and boat crossing challenges. You follow the old quarryman's footsteps through authentic tunnels and caverns, with safety anchors added where necessary and all challenges avoidable by scrambling around them instead. Headtorches, helmets, harnesses and lanyards are provided. You bring your own waterproofs, warm clothes and wellies (or request wellies 48 hours ahead). A live English-speaking guide leads groups. Children from age 8 are welcome when accompanied by a parent or guardian.

The experience

You start with a 30-minute uphill walk to reach the mine entrance in Snowdonia, then spend the next few hours underground following passages the slate quarrymen carved decades ago. The only light comes from your headtorch. Along the way you'll encounter a series of optional challenges: climbing sections, an abseil, a short tyrolean (zipline) and a brief boat crossing. None of them are mandatory (you can scramble around any obstacle instead), so the difficulty is yours to set. A guide leads the group and can share the history of how these caverns formed if you're interested.

This is caving with safety anchors bolted in where the mine needed them. The operator has changed almost nothing else about the space, so what you're moving through is the real thing: tight passages, uneven ground, water underfoot. The experience suits families and school groups as much as couples and adult parties looking for a challenge. When you emerge near the top of the mountain at the end, you walk back down with views across Snowdonia if the weather holds.

What’s included

• Safety equipment including helmet, headtorch, harness and lanyard.
• a live English-speaking guide.
• the 30-minute approach walk and the underground exploration with optional climbing, abseil, short zipline and boat crossing.

Before you book

Days and timesThursday to Sunday5 departure times: the first at 09:30, the last at 19:00

AgesAdult (18 to 90 years) · Youth (8 to 17 years) · Under 8: can't be booked

GroupUp to 12

Live guideEnglish

Meeting point and pickupNo hotel pickup: you go to the meeting point. Ends back at the starting point.

Cancellation and refundsFree cancellation up to 24 h before the start. After that, no refund.It may be canceled due to bad weather or if the minimum number of travelers isn't reached. If that happens, you're offered another date or a refund.

Prices and times updated yesterday

Good to know

Moderate physical effortNot recommended during pregnancyNot recommended with back problems

Operated by Adventure Activities Wales

Is this one for you?The activity starts with a 30-minute uphill walk from the mine entrance in Snowdonia, so you'll need to arrange your own transport to the trailhead or book a separate transfer if you're without a car. Once there, the guide leads the whole group through the mine and back down, so no navigation or planning is needed underground.

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Top questions

Can children come?

Yes. Ticket types: Youth (8 to 17 years). Children under 8 can't be included in the booking.

What happens if it rains?

It may be canceled due to bad weather. If that happens, you're offered another date or a refund. Free cancellation up to 24 h before the start.

What do I need to bring for the underground adventure?

Waterproofs and warm clothes are essential. Wellies are recommended but can be requested 48 hours in advance if you don't have them. The operator provides helmets, headtorches, harnesses and lanyards, so you don't need to bring safety gear.

What happens if I don't want to do the climbing, abseil or zipline?

Every challenge (the climbing, abseil, short zipline and boat crossing) can be avoided by scrambling around it instead, so you set your own level of difficulty as you move through the mine.

How long does the activity take including the walk to the mine?

The total time is five hours: about 30 minutes walking uphill to reach the mine entrance, then the underground exploration, then the walk back down from near the mountain top.

Is there anything I shouldn't do before booking?

The activity is not recommended for travelers with spinal injuries or pregnant travelers. You should have at least a moderate level of physical fitness to manage the terrain and the optional challenges.