Glendalough Upper Lake
Glendalough Upper Lake is one of Ireland's most breathtaking and historically resonant places, nestled deep within a glacial valley in the Wicklow Mountains National Park. Sitting at the western end of the Glendalough valley in County Wicklow, the Upper Lake is the larger and more remote of the two lakes that give the valley its name — "Gleann Dá Loch" meaning "valley of the two lakes" in Irish. Fed by mountain streams cascading down from the surrounding peaks, it stretches beneath towering cliffs and ancient oak woodlands, offering a landscape of raw, unhurried beauty that draws visitors from across Ireland and around the world. The combination of natural grandeur and early medieval monastic heritage makes this one of the most compelling sites in the entire country.
The spiritual and historical weight of Glendalough is inseparable from the figure of Saint Kevin, a sixth-century monk who sought solitude in this remote valley around 498 AD. According to tradition, Kevin retreated here to live as a hermit, initially inhabiting a tiny cave hewn into the cliff face on the south shore of the Upper Lake — a place still known as St Kevin's Bed, accessible only by boat or by a narrow ledge. Legend holds that Kevin was so still in prayer that a blackbird built a nest in his outstretched hand and he remained motionless until her eggs hatched. His reputation for sanctity attracted disciples, and what began as a hermitage grew into one of early medieval Ireland's most important monastic settlements. After Kevin's death around 618 AD, the monastery flourished for centuries, becoming a major centre of learning, manuscript production, and pilgrimage. It was raided repeatedly by Vikings during the ninth and tenth centuries, and later attacked by Anglo-Norman forces, but the community endured until the monastery's formal dissolution in the sixteenth century.
The physical character of the Upper Lake is quite different from the more accessible Lower Lake and the celebrated monastic city near the valley entrance. At the Upper Lake, the valley closes in dramatically, with steep, forested slopes rising sharply on both sides and the rugged quartzite ridges of mountains like Camaderry and Lugduff forming a natural amphitheatre above. The lake surface is dark and reflective, mirroring the surrounding cliffs and trees in calm conditions. The air here tends to be cool, damp, and fragrant with the smell of moss, lichen, and the distinctive mustiness of ancient oak woodland. Sounds are dominated by birdsong, the trickle of streams, and occasional waterfalls — particularly the impressive cascade of the Poulanass waterfall nearby — along with the lapping of water at the rocky shoreline. On misty mornings, low cloud clings to the cliff faces and filters through the trees, giving the valley an otherworldly, almost timeless quality.
On the southern shore of the Upper Lake, the remnants of the original monastic settlement associated with Saint Kevin himself are more intimate and atmospheric than the better-known ruins downstream. Here you find the Reefert Church, a small but beautifully preserved Romanesque building whose name derives from the Irish "Rígh Fearta," meaning "burial place of the kings," suggesting it was the burial ground of the kings of Leinster. Nearby stands Temple na Skellig, perched on a ledge above the lake and reachable only by clambering along a rough path. The cliffside cave of St Kevin's Bed sits some thirty feet above the lake surface, accessible to those willing to take the boat trip offered during summer months. These upper lake sites feel considerably more remote and contemplative than the busier main monastic city near the lower lake.
The surrounding landscape is part of Wicklow Mountains National Park, the largest national park in Ireland, encompassing over 20,000 hectares of upland bog, heath, and glaciated valleys. The glacial origins of the Glendalough valley are evident everywhere: the steep, smooth cliff faces, the U-shaped profile of the valley, and the two lakes themselves are all classic features of glacial erosion. Above the treeline, open moorland stretches toward summits including Camaderry at 698 metres, which offers panoramic views of the valley and the Irish Sea on clear days. The valley is home to significant wildlife, including red deer, red squirrels, peregrine falcons, and the endangered freshwater pearl mussel in the lake itself. The woodland along the shores contains some of Ireland's finest sessile oak forest, designated as a Special Area of Conservation.
Visiting the Upper Lake requires a short walk from the main visitor facilities, which adds to its sense of separation and reward. From the main Glendalough car park and visitor centre near the Lower Lake, a well-maintained trail follows the valley floor westward for roughly one kilometre, passing the Green Road and the Poulanass waterfall before reaching the upper lake shoreline and the Reefert Church ruins. The walk is manageable for most people, though the terrain around the upper lakeshore and the paths climbing toward St Kevin's Bed and Temple na Skellig are rougher and require more care. The site is managed by the National Parks and Wildlife Service and by the Office of Public Works. There is no vehicle access to the Upper Lake itself; all visitors must walk from the main car park or approach via one of the marked walking trails that descend from the surrounding mountains.
The best times to visit are typically spring and autumn. In late April and May, the valley's oak woodland bursts into fresh green leaf and birdsong is at its most abundant, while autumn brings spectacular golden and russet colours to the trees against the dark water of the lake. Summer is by far the busiest season — Glendalough receives around a million visitors per year and the main monastic city and car parks can become crowded, particularly on weekends. A weekday visit or an early-morning arrival substantially improves the experience. Winter visits, though demanding in terms of weather and short daylight hours, can offer extraordinary atmosphere, with frost on the reed beds, long shadows on the cliff faces, and the chance of having the upper valley almost entirely to oneself. The upper lake shore and its ruins are freely accessible year-round at all hours.
One of the more unusual and little-known aspects of the Upper Lake is its role in the local tradition of pilgrimage known as the "Pattern of Glendalough," historically held on the feast day of Saint Kevin, June 3rd. Pilgrims would walk a circuit of the sacred sites around both lakes, visiting stations associated with Kevin's life and performing prescribed prayers and rituals. The pattern attracted enormous crowds in earlier centuries, though it also acquired a reputation for revelry and was eventually suppressed by the Catholic Church in the early nineteenth century. The lake water itself was considered to have healing properties, and pilgrims would bathe in it or carry it away. The spiritual memory of this landscape as a place of Christian contemplation, retreat, and healing has persisted continuously since the sixth century, making the Upper Lake one of the longest-unbroken sites of spiritual practice in Ireland, and indeed in the British Isles.