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In Glendalough lived an ould saint

Renowned for his learning and piety

His manners were curious and quaint

And he looked upon girls with disparity

Glendalough is one of the most picturesque spots in Ireland, a deep, dark valley surrounded by wooded mountains. This is a spectacular example of a 'U valley' carved out by a glacier in one of the Ice Ages. The name Glendalough means 'Valley of the Two Lakes'. The Upper Lake is by far the bigger, being about ten times the size of the Lower Lake.

Just down the valley from the Lower Lake are the ruins of the Monastic Village - this was one of the major monasteries of Ireland in the 1st Millennium AD. It is said to have been founded by Saint Kevin (Cóemgen in Old Irish, Caoimhín in Modern Irish) in the 6th Century. Today, there's a large graveyard with a number of ancient buildings and ruins. Just outside the remains of the Monastic Village, there is the modern village of Glendalough with pubs, a hotel and a Visitor Centre where you will find exhibitions explaining the history of the area.

Glendalough is a very popular tourist destination, one of the most popular in Ireland. If you're driving, there are two large car parks, one at the Upper Lake and the other at the Visitor Centre, but these fill up early at the weekend. Try to get there by 11am at the latest. There's a fee of €4 for the day in the Upper Lake car park throughout the year; the Visitor Centre car park is free in the off season but also charges €4 for the day in the summer. It's also possible to reach Glendalough by the St Kevin's Bus, which leaves St Stephen's Green in Dublin every day at 11:30am and takes about 90 minutes.

There are nine marked walking routes in the area, ranging from one to 11 kilometres in distance and with difficulty levels from 'Easy' to 'Hillwalk' - one of the longer of these trails is the Spinc Loop Walk described in this entry.

The Spinc Walk

The Spinc Walk is quite a difficult one - it is only 9.5km (5.9 miles) in total if you start at the Upper Lake car park, but there is a strenuous climb:

• The total ascent is 366m (1,200 feet).
• Half of this is in the first 2km (1.3 miles).
• This half includes a challenging set of steps: 600 of them rising 86m (280 feet). That's the equivalent of climbing a 30-storey building.

Thankfully, for most of the walk, the surface underfoot is very straightforward. For about a quarter of the trail you are on a boardwalk - a path made from railway sleepers and dotted with metal staples and chicken-wire to give a good grip, so you can lope along. About 2–3km of the route is rough stones and care must be taken descending the steep sections of this.

It sounds difficult but it is well worth it as the views along the way are some of the best in Wicklow.

Starting Off

If you're parked at the Visitor Centre, follow the signposts towards the Upper Lake. Where the trail splits, you can take either the Green Road or the Boardwalk route - the former is slightly shorter but the latter is more interesting - it crosses marshland and offers an opportunity to see some wildlife, such as deer, rabbits, herons, damselflies and dragonflies.

Distances in this entry are given in kilometres from the Upper Lake car park. If you have a smartphone capable of measuring distance, you can use the distances given here to check you are on track.

At the Upper Lake car park [0.0km], walk down to the Upper Lake and admire the view. To the left of the lake you can see the cliffs and steep slopes of a mountain. This is called the Spinc: you're going to climb it and walk along the top of those cliffs. At the far end of the lake you may be able to see a waterfall - you'll come down from the cliffs to this waterfall and return along the bottom of the valley to the right of the lake.

Now turn left, so that the lake is on your right, and look for the trail up to Poulanass Waterfall. This is clearly marked, and also has arrows for the many walking trails that start along this route. The one we'll be following is the White Arrow Trail.

The Climb

[0.4km] The first part of the trail is through pleasant oak forest. These oak trees are not very tall, as they used to be coppiced - this method of woodland management involves regularly cutting the trees back right down to near ground level and letting them regrow. As a result, the trees grow with many narrow straight trunks rather than one thick one. This practice is no longer carried out here, but none of the trees have yet reached the full height of a mature oak, which takes about 300 years.

The path climbs beside the small Lugduff Brook, which has lots of pools and small waterfalls. The biggest of these is called Poulanass, which means 'The Hole of the Waterfall'. The path eventually comes out onto a forest road at a bridge [0.8km]. Following the arrows, turn right here and follow the forest road.

Although the native forest of Ireland in the past was oak, it is very slow-growing. The State-owned company Coillte ('kweelcha') is in the business of making money by growing trees on much of the wild, abandoned land of Ireland. They've discovered that many of the coniferous trees of Northern Europe and Scandinavia grow very well in this country, and the trees can grow all the year round because winters are mild. There is quite an industry in planting and felling these coniferous forests.

All the forest you will encounter from this point of the trail onwards is coniferous. Unfortunately, the coniferous forests are very boring to walk in. The trees produce resinous needles instead of leaves - these cover the ground underneath, generally preventing any smaller plants from growing. Luckily, you won't be in the boring forest for too long.

Soon you come to the 600 steps [1.4km]. These are made from wooden railway sleepers and are coated with metal nails so that they offer good grip underfoot. The climb is strenuous, but there are plenty of places where you can step to one side and rest, letting faster walkers pass you.

The Clifftop Boardwalk

At the top of the steps [1.8km], there is a short flat section and then you come out of the forest to an impressive view. You are at the top of the Spinc, looking down on the valley. You can see a small portion of the Upper Lake below you, and further down the valley the smaller Lower Lake. Beyond the Lower Lake is the round tower of the Monastic Village.

The next 3km of the walk is along a 'boardwalk', a path along the clifftop made from railway sleepers. It is only two sleepers wide so you must walk single file. If you want to pass someone, you must step off the path, but be careful doing this, as in some places the ground is very wet.

The path starts fairly level and gives good views down into the valley. Then it begins to climb and gradually ascends by the same amount again as you have already climbed since the car park. This doesn't feel as bad, though, because it is over a longer distance.

The Blanket Bog

Once you reach the highest point of the walk [3.9km] and the boardwalk starts to descend, the land becomes very bare around it. You are crossing a 'blanket bog'.

The blanket bog is dominated by sphagnum moss. This is a plant which is very tolerant of wet ground. It grows, soaks up moisture, dies and decays very slowly continuing to retain the moisture. This means the ground gets wetter and other plants are discouraged from growing, making the ground even more suitable for the sphagnum moss. Over thousands of years the decayed moss forms into peat (known in Ireland as turf). This brown, clay-like substance can be dried and used as fuel or as a major ingredient of gardening compost and soil conditioner.

There are other plants that grow on the bog besides the moss that forms it: heather, grasses growing in clumps, fraughan/bilberry (a small bush with black berries similar to small blueberries) and moisture-loving plants such as liverworts and sundews. The blanket bog continues to grow slowly until the layer of peat can be many metres deep. Depending on the amount of moisture, it can be solid enough to walk across, or soft enough to sink into.

The boardwalk crosses the bog and you'll be safe as long as you stick to it, but you should check very carefully before stepping off the planks.

The Stone Road

At 4.8km, you reach the end of the boardwalk and step onto a rough stone path. The path descends into Glenealo Valley, the valley at the end of Glendalough. You soon arrive at some old stone buildings [5.2km]. These are the remains of a 19th-Century lead mine known as 'Van Diemen's Land' due to its remoteness.

The mountains of Wicklow are mostly granite and were formed about 440 million years ago. Wicklow at the time was on a continent called Avalonia which due to tectonic movements crashed into North America. The stress of this collision caused a large crack through which molten granite erupted from deep in the Earth. As the granite cooled, cracks appeared in it and hot rivers of high-pressure water flowed through the cracks. Where these rivers cooled slightly, they deposited heavy metal ores such as lead, zinc, silver and gold. These deposits were far under the surface of the earth.

Then far more recently, only about 20,000 years ago, Ireland experienced an Ice Age - most of the country was under a huge sheet of ice, up to 900m thick and similar to the one on Greenland. Movements of this ice ground down the tops of most of the Wicklow Mountains, so they almost all have rounded shapes and look more like hills than mountains. At some point during the Ice Age, the upper mountains were clear of ice, but a giant glacier sat where the valley of Glendalough is now, gradually cutting out and deepening the valley into its present U-cross-sectioned shape.

The action of the ice brought the mineral deposits much closer to the surface. In the late 18th Century someone found a gold nugget in a stream in southern Wicklow and there was a mini Gold Rush, but the gold turned out to be non-workable. Nevertheless, the mineral wealth of the county became recognised and in the 19th Century, many mines were worked in Wicklow. The most important of these were the ones in Glendalough and the adjacent valley of Glendasan. The mine buildings you see here are small, but you'll soon encounter a much bigger mining village.

The path crosses the Glenealo River on a sturdy wooden footbridge [5.4km], then turns right and descends beside the river. You're now looking straight down the valley of Glendalough and the views are spectacular.

The path descends in a series of zigzags. At the bottom of the slope, there is a much bigger Miner's Village [7.0km], with many 19th-Century buildings, and with large slag heaps. This was primarily a lead mine, although some zinc and a very small amount of silver were also mined. Due to the lead, nothing grows on the slag heaps even now more than a century after the mine was closed.

The Return by the Lake

As you leave the Miner's Village, you will see a marshy area on the right at the end of the Upper Lake. This is a good area to see dragonflies.

The path, now known as the Miners' Road, continues through a small forest on the left side of the lake. About three quarters of the way along the lake [8.9km approx], you should be able to see a small square hole in the cliff on the other side. This is a man-made cave known as St Kevin's Bed. Legend has it that the saint lived here as a hermit before he founded the monastery. It's not known who made the cave or why, but it is believed to date from long before the time of St Kevin. St Kevin's Bed is not accessible to the public, as a rock-climb across a sheer cliff is needed to get to it. Many tourists were injured in the past attempting this climb.

The path returns across a bridge to the Upper Lake car park which is the end of the walk [9.5km]. There are often stalls here where you can get some food, or you can continue on to the village of Glendalough.

The Monastic Village

If you haven't already seen it, you may like to wander down to the Monastic Village. This was one of the most important monasteries in Ireland up to the arrival of the Normans in 1169.

The Monastic Village is now a cemetery, and most of the graves in the cemetery are modern ones from the last couple of centuries. There are, however, a few things in the cemetery that are very old:

• The entrance from Glendalough Village is a strange double gateway.
• The round tower is one of the best in Ireland, although the conical roof is not original.
• The Cathedral is the largest ruin in the graveyard and was the main church of the monastery.
• There is a High Cross but it has been moved into the Visitor Centre to protect it from the elements and from vandalism. It's not a very impressive example of a High Cross, being mainly unadorned, but it is very old.
• St Kevin's Chapel - this small church is unusual in that it has its own round tower built into the structure. Probably the only church like it in Ireland is in the monastery of Clonmacnoise in Offaly.

There are other ancient monastic ruins outside of the cemetery, but they are mainly just low walls and foundations.