Rocky Valley & St Nectan's Glen Hike near Tintagel, Cornwall

I went to St Nectan’s Glen because a photograph wouldn’t leave me alone.

I’d seen it online — a waterfall dropping through a hole it had carved for itself in solid rock, framed like a window into another world — and I couldn’t accept that it was real until I stood in front of it myself. It looks like somewhere a fantasy novelist invented and then forgot to tell anyone that it was fictional.

The Rocky Valley and St Nectan’s Glen hike connects this waterfall to some of the most dramatic coastal scenery in Cornwall. Clifftops above Merlin’s Cave, a river gorge carved deep into the rock, and a set of ancient petroglyphs that nobody has been able to fully explain. I did this as a modified route from Tintagel Castle, without a car and without a particularly rigid plan, sometime around 2015 or 2016, before smartwatches and recorded routes were part of how I hiked. What I have instead are very clear memories — and a film photograph of St Nectan’s Kieve that has been on my wall ever since, and that strangers ask about more than any other image I own.

Rocky Valley & St Nectan’s Glen Trail Summary

Start: Trethevy village (standard) or Tintagel Castle (modified, car-free)

Distance: ~11.9 km (7.4 mi)

Elevation Gain: ~408 m (1,338 ft)

Terrain: Coastal clifftop path, woodland trail, rocky gorge, some road sections

Type: Circular

Time: 3.5–4 hours walking, more with stops

Entry fee: St Nectan’s Glen charges entry (10 pounds) — includes wellies for the wet path to the falls

Footwear: Waterproof hiking boots strongly recommended — muddy in sections year-round

AllTrails route: St Nectan’s Glen, Tintagel Castle and Rocky Valley Circular

A Bit of Background

This corner of north Cornwall sits within the Cornwall Area of Outstanding Natural Beauty, which is a designation that understates things considerably. The coastline here is part of the South West Coast Path — Britain’s longest national trail — and the stretch between Tintagel and Boscastle is among its most dramatic. Inland, the River Trevillet has spent centuries cutting its way through the rock toward the sea, carving Rocky Valley in the process and leaving behind a landscape that feels ancient in a way that goes beyond geology.

The area around Tintagel has drawn people seeking something for a very long time — Arthurian pilgrims, early Christian saints, Bronze Age communities, and today, neo-pagans and spiritual visitors who make the Rocky Valley petroglyphs a modern place of offering. There is something in this landscape that keeps pulling people in. Having walked it, I understand why.

THE WALK

From Tintagel Castle

The standard route begins in Trethevy village, but if you’re based in Tintagel without a car, starting from the castle works well and adds a natural opening chapter to the day. From the castle, you pick up the South West Coast Path heading northeast — and almost immediately, the scale of what you’re walking through becomes clear.

The cliffs here drop sharply to the Atlantic below, and the path runs close enough to the edge that you feel the exposure. Looking back toward the castle from this angle, it sits on its outcrop the way it must have always looked — remote, almost implausible, jutting out against the grey-blue sea. Further along the path, the coastline comes into view properly: headlands extending into the water like fingers, the waves hitting the base of the cliffs with a force that seems disproportionate to the apparently calm day above. Merlin’s Cave is visible in the rock face below — dark, wet, and exactly as atmospheric as the legend requires.

Rocky Valley

The path eventually descends into Rocky Valley, where the River Trevillet meets the sea after cutting its way through the rock. The valley is steep-sided and narrow, the river audible before it’s visible, and there is a moment on the way down where you think — just briefly — what exactly have I got myself into. There are rocky sections, uneven footing, and a drop in the path that requires some attention. Once you’re down in it, that uncertainty dissolves completely.

The gorge is wonderful. The river has carved the rock into jagged, layered formations — deep and dramatic and damp — and standing at the bottom of it, surrounded by walls of stone with the water running fast beside you, it feels like a genuinely secret place despite being a well-marked trail. The sound of the water fills the whole space.

The Petroglyphs at Trewethett Mill

Before the valley opens up, the ruins of Trewethett Mill appear on the path. Stop here and look carefully at the shale cliff face nearby — this is where the Rocky Valley Labyrinths are, and they are easy to miss if you don’t know to look.

Two classical seven-circuit maze patterns are carved into the rock. They were rediscovered in 1948, and since then their origins have been genuinely, productively debated — Bronze Age sacred symbols, Celtic carvings, 18th-century mill worker graffiti — with no consensus reached. I had no idea they were there. I saw something that caught my eye, crouched closer, and spent several minutes trying to confirm to myself that what I was looking at was real and old and intentional before I found the information signs nearby. The archaeologist instinct — I spent every available elective in nursing school studying archaeology — kicked in hard. I wanted to know everything immediately, and the signs only scratched the surface.

In the cracks of the mill ruins and the nearby trees, I noticed small offerings — ribbons, twigs, arrangements that I initially read as memorials. They weren’t. The site has become a quiet pilgrimage destination for neo-pagans and spiritual visitors, and the offerings are tributes rather than remembrances. Knowing that changes how you read the place — it has been meaningful to people across an enormous span of time, and it’s still meaningful now, just to different people for different reasons.

Tip: Look for the carvings before you read the signs — the experience of trying to work out what you’re looking at first is worth having.

The Forest Path to St Nectan’s Glen

From Rocky Valley, the route moves inland and into woodland. The forest here has that quality that good forests always have — moss on everything, damp earth underfoot, light coming through the canopy in shifting pieces. It reminded me of PNW forest in its atmosphere: the same sense of being enclosed by something alive and old, though the tree varieties and undergrowth are distinctly different, and the smell is its own thing — damp and earthy but with a particular sweetness underneath that I associate entirely with this walk.

I was full of anticipation on this stretch, and also quietly nervous that the waterfall wouldn’t live up to what I’d seen in photographs. That anxiety is worth naming because it’s real: some places genuinely cannot compete with their own best images. St Nectan’s Glen is not one of those places.

St Nectan’s Kieve

There is an entry fee to access the falls — pay it. It includes wellies for the wet, mossy path down to the water, which you will need.

St Nectan’s Kieve is a 60-foot waterfall that drops through a hole it has carved for itself in the rock face — a natural arch formed by centuries of water finding the path of least resistance through solid stone. You don’t see the falls and then the hole. You see the whole thing at once: water appearing above, dropping through the frame of rock, disappearing into the pool below. It looks like something designed. It isn’t. It just happened, slowly, over more time than is easy to comprehend.

The glen surrounding it is moss-covered and enclosed, the light filtering through the tree canopy in the dappled, shifting way that makes everything look slightly illuminated from within. The air smells of damp earth and cold water and clean things. There were very few other people there when I arrived, and for a stretch, I had the falls almost entirely to myself.

I’ve loved waterfalls my whole life, and I’ve stood in front of a lot of them. This one is different. I stayed longer than I planned. I took a lot of photographs, including the film photograph that has been on my wall ever since. I didn’t want to leave, which is usually the sign that a place has done something to you that you won’t be able to fully explain later.

I still can’t fully explain it. I’d go back tomorrow.

PLAN THIS TRIP

The Rocky Valley and St Nectan’s Glen walk connects naturally to a two-day Tintagel stay — see the full Tintagel destination post here: 2 Days in Tintagel: Where Folklore Meets the Sea. The walk can be done independently of the village without a car, which is how I did it.

St Nectan’s Glen entry tickets — check opening times and book ahead in peak season
AllTrails route map: St Nectan’s Glen, Tintagel Castle and Rocky Valley Circular

This is a full half-day to full-day walk, depending on your pace and how long you linger at the falls. I’d strongly recommend building the afternoon around St Nectan’s Glen rather than treating it as a quick stop — the café at the entrance is a good place to decompress before or after, and the walk back through the forest deserves the same unhurried attention as the walk in.

TIPS FOR THE WALK

Waterproof hiking boots are strongly recommended — the trail is muddy in sections year-round, and the path to the falls is wet regardless of weather
Entry fee applies at St Nectan’s Glen — it covers access and wellies; check current pricing before you go, as it has increased in recent years
The petroglyphs are easy to miss — slow down at Trewethett Mill ruins and look carefully at the shale cliff face before consulting the signs
Go early or off-season for the best chance of solitude at the falls — the magical quality of St Nectan’s Glen is significantly tied to quiet
The coastal section is exposed — wind and conditions can change fast, especially near the cliff edge above Merlin’s Cave
Car-free visitors can start from Tintagel Castle and join the South West Coast Path from there — the route is well signposted and manageable with Google Maps as backup