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The Snowdon Nantlle Challenge is an exhilirating hillwalking adventure in the heart of Snowdonia National Park.

Starting & finishing at the Rhyd Ddu Car Park on the A4085 at the foot of Snowdon’s western slopes, the event consists of two scenic but contrasting loops covering 40 kilometres with 2,500 metres of ascent.

We first complete a circular route on two of Snowdon's quietest & most scenic paths, before heading off the beaten track & delving deep into north Wales history with our second loop leading us through the ruins of Glanrafon Slate Quarry, Cwm Dyfor Copper Mine & the Prince of Wales Slate Quarry at the head of Cwm Pennant.

Snowdon Nantlle Challenge

Challenging, fun, and safe. Over the weekend, we learned a lot about both walking on the mountains and about ourselves. Inspire Alpine's experience and support allowed us to completely focus on the challenge and forget about the route and logistics.

- Jonathan, Challenge participant

We ascend Snowdon up the Rhyd Ddu path, then descend the Snowdon Ranger path. On descent, we divert off the track to take in the summits of Moel Cynghorion (674 metres) & Foel Goch (605 metres), before cutting back across to Rhd Ddu on public rights of way to our support vehicle. After refreshments, we head west to take on the Nantlle Ridge, a classic ridge walk, which is exhilarating but not as technical as Crib Goch or Tryfan, and not nearly as exposed. We return to Ryhd Ddu via Cwm Dwyfor.

Once you've booked, you’ll be sent joining instructions, a training plan and kit list. We can also provide advice on local accommodation and other activities.

Dates & Booking

This is your opportunity to join a group (maximum of 12 people) on a superb Snowdonia mountain challenge off the beaten track, guided by experienced Mountain Leaders. We run open throughout the summer. Individuals or groups are welcome to join us. You can view available dates on the dropdown below, then select your ticket type.

Self-funding £125: Make full payment of £125 (option 1)

Fundraising: Pay a non-refundable registration fee of £50 & choose to raise a minimum of £150 for our social mission and set up a fundraising page on our site (option 3)

Once you've booked, you'll receive an email acknowledging receipt of your booking and you'll receive a second email requiring you to complete our online UK Trip Booking & Medical Declaration Form, which must be completed by each participant before we can confirm your place. You'll also need to read and agree to our Participation Agreement & you'll be asked to sign to confirm this when you submit your medical details.

Participation Agreement 

After we confirm your booking we'll send you full joining instructions, a training plan and a kit list. We can also provide advice on local accommodation and other activities.

Please contact us for pricing for private guiding.


VERY HARD / EXTREME: The Snowdon Nantlle Challenge is very demanding and requires a high level of fitness & commitment and you must be able to walk for up to 14-hours over mountainous terrain. We cover the same distance as the Yorkshire Three Peaks (40 km), but with 800 metres more ascent & some pathless sections. For mixed ability groups we offer the option for less fit participants to complete the Snowdon loop only, which is a great challenge in itself (17.5 km & 1,250 m ascent).

Fundraise for us

Fundraising for us can make your bucket list adventure much more achieveable & make your dreams come true! With this option, you pay your non-refundable registration fee of £50 when booking 'Option 2 - Fundraising' from the options above to reserve your place. You're pledging to raise £150 for our social projects and this option means the balance of your adventure challenge cost is met through this minimum sponsorship.

Read more about fundraising

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Where & when does it start?

Our meeting time is 06.30 am. The walk starts and finishes at the public car park at Rhyd Ddu.

Postcode:        LL54 6TN

What3words:  ///clip.ratio.junction

OS Grid Ref:    SH 571 526

Please note the car park charges are as follows:

  • Up to 4 hours: £3.00
  • Over 4 hours: £6.00

The car park ticket machines accept coins or cards.

Route Map & Altitude Profile

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These outline timings are a guide only.

Time  Activity 
05:45 Meet guide/s at our Rhyd Ddu car park start point
06:00 Start the Snowdon Nantlle Challenge with an ascent of Snowdon on the Rhyd Ddu path
09:00 Snowdon summit (1,085 m / 6 km)
10:30 Moel Cynghorion summit (674 m / 10 km)
11:00 Foel Goch (605 m / 12.5 km)
12:30 Arrive into Rhyd Ddu car park to meet support vehicle & refuel (187 m / 18.5 km)
13:00 Depart Rhyd Ddu car park for ascent of Y Garn
14:00 Y Garn summit (633 m / 20 km)
14:30 Mynydd Drws-y-coed summit (693 m / 21.5 km)
14:45 Mynydd Tal-y-mignedd summit (653 m / 22.5 km)
15:45 Craig Cwm Silyn (734 m / 25.5 km)
16:15 Garnedd Goch (700 m / 27.5 km)
17:00 Bwlch Dros-bern (515 m / 30.5 km)
19:00 Rhyd Ddu car park end point (39 km)

Route Details

Loop 1: Snowdon loop

We begin by ascending Snowdon on the Rhyd Ddu path, the quietest and most scenic of the six main routes to the summit, with great views towards Moel Hebog and the hills of Nantlle.

The path initially follows the old track that served the Bwlch Cwm Llan slate quarry, then leaves the track to climb quite steeply over rocky terrain to Llechog ridge. The path then follows the ridge over bare and exposed ground on a narrow and rocky path with steep slopes to the left below, so extreme care is taken on this section.

The path continues to the junction with the south ridge and along to Bwlch Main, with tremendous views over to the Watkin path and Y Lliwedd beyond, before the final climb to the summit.

We descend via the Snowdon Ranger path to Bwlch Cwm Brwynog, where we ascend the fence-line to Moel Cynghorion (674 m). We descend grassy slopes along the fence-line via Bwlch Carreg y Gigran to join the steep path up to Foel Goch (605 m).

We then drop back down to cross the Snowdon Ranger path and pick up a public right of way with old way-markers marking the path. The route passes through the disused Glanrafon Slate Quarry and then over rough ground to meet a newly built path that returns us to Rhyd Ddu, where we can resupply at our support vehicle.

Loop 2: Nantlle Ridge Loop

The Nantlle Ridge scramble from Rhyd Ddu is undoubtedly one of the classic ridge walking routes in Snowdonia.

We begin by heading west across the A4085 to begin a steep ascent of around about 450 metres to our first summit Y Garn (633 m), where the path veers right to the summit. From here, weather permitting, we’ll have great views of the ridge ahead, and of Mynydd Mawr across the valley.

The scrambling then begins, although most of the difficulties can be avoided on the left had side. After the scrambling sections, the route eases off to become an enjoyable & scenic ridge walk.

From Drws y Coed, we follow a grassy ridge and staying on the crest as much as possible, up to the top of Trum y Ddysgl, before we drop back down across a broken, grassy ridge to the obelisk at Mynydd Tal-y-Mignedd.

We descend on a steep, broken path to Bwlch Dros-bern before a rough walk/scramble on an indistinct path to the summit of Craig Cwm Silyn (734 m), which marks the highest point on the Nantlle Ridge.

We continue to Garnedd Goch (700 m), which is really still part of Craig Cwm Silyn & the 3rd highest point on the ridge. The summit is strewn with rock debris and has a trig point and a cairn.

We then backtrack to descend Craig Cwm Silyn and down to Bwlch Dros-bern. From here, we leave the ridge and drop south east on pathless terrain to contour towards the top of an old tramway on an incline that was built for the ill-fated Cwm Dwyfor Copper Mine, which was abandoned in 1878

We follow the incline and rights of way on boggy ground, before the path becomes very obvious and leads up through the Prince of Wales Slate Quarry at the head of Cwm Pennant to Bwlch-y-Ddwy-elor. At its peak, the quarry employed 200 men producing 5,000 tons of slate per annum 

From here, we drop into Beddgelert forest and back onto open hillside where we follow a good footpath for the last couple of kilometres back to our starting point to finish the challenge.

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Weather & terrain

The weather in the Welsh mountains is prone to change rapidly - it's essential that you're prepared & equipped for a range of mountain weather conditions including rain, wind and heat.

Your safety and wellbeing is our top priority at all times & our Leaders have sole authority to modify the itinerary at any time before & during the event if weather or ground conditions are unsafe. In those circumstances, we'll make alternative arrangements to maintain the integrity of the event itinerary.

The terrain of the Snowdon Nantlle challenge includes well-worn paths, boggy areas (particularly after rain), steep ascents and descents. Poor weather makes the walk harder and it’s essential that participants have good footwear and adequate outdoor clothing to protect you from the elements.
Snowdonia Mountain Forecast

Water on your walk

We recommend a Water-to-Go filter water bottle for this event - it saves you carrying extra weight on this long hill day and you can fill up safely and drink water from the streams on the route.

What’s included?

  • Mountain Leaders on a 1:10 ratio
  • Support Vehicle at Rhyd Ddu with snacks & water
  • Access to Vamoos travel app with full event details offline
  • Live GPS tracking & shareable links for family/friends
  • 20% discount for Montane
  • 15% discount for Cotswold Outdoor
  • 15% discount for Open Air
  • 20% discount on Water-to-Go bottles
  • 25% discount on Uphill Athlete training plans
  • Digital Finisher's badge
  • Access to our inspirational 'Follow Your Dreams' Everest webinar

What’s Excluded? 

  • Accommodation (but we can provide advice on options & we can provide discounted accommodation for up to 10 people at Vale View Luxury BnB at extra cost)
  • Transport to/from your accommodation to our event meet point
  • Personal Food & Drink
  • Parking Charges

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Your safety is our top priority. Our activities are fully risk assessed and we hold Public Liability Insurance via Lockton LLP. Our leaders carry a mountain first aid kit, an emergency shelter, a fully charged mobile phone & spare battery, spare warm clothing & emergency food and we have two-way radio contact with all of our guides at all times during an event. We also hold a Public Service Vehicle (PSV) Operator Licence.


A full kit list will be provided when you register for the Snowdon Nantlle Challenge. Good kit will make the difference between a brilliant mountain experience and an uncomfortable one. Footwear should be well worn in and you need to bring good quality waterproofs (jacket & trousers). We provide a range of disocunt codes for kit suppliers, including Montane, Cotswold Outdoor & Open Air.

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