Overview
Sixteen stone bridges cross the Shimna inside Tollymore Forest Park, the oldest of them built in 1726. After a couple of dry weeks the river under them is a clear step-and-pool stream you could pick your way across; two days of Mourne rain later it is a brown roar you can hear from the car park. That is the whole character of the place: the Shimna (Irish: Simhné, the river of bulrushes) is a spate river, rising fast and falling fast, and it is a different animal depending on when you catch it.
It runs 11.77 km (about 7.3 miles) from the slopes of Ott Mountain, high in the Mournes, down to Dundrum Bay and the Irish Sea at Newcastle, County Down. The river and its main tributary, the Trassey, are an Area of Special Scientific Interest for their rock formations and riverside plant and animal life. If you only have half an hour, walk from the forest’s main gate down to Parnell Bridge and back: it takes in the bridges, the tree cover and the loudest of the cascades without committing you to a full loop.
History & heritage
Flint tools from the Mesolithic and Bronze Age have been found on the floodplain, evidence that people were living off the river’s water and fish thousands of years ago. Its strategic value carried into the 16th century: Felix Magennis built a castle near the mouth in 1588, demolished in 1830.
The bridges are the visible legacy. James Hamilton laid out Tollymore as a landscape garden, and between 1726 and 1842 sixteen stone bridges went up across the Shimna. The Old Bridge (1726) is the earliest; the ivy-clad Ivy Bridge (1780), Foley’s Bridge (1787) and Parnell Bridge (1842) are the ones people photograph. Above the river Hamilton also built the Hermitage, a small stone shelter set into the gorge in the 1770s so that ladies could sit out of the weather while the men fished below. More recently the forest and the river stood in for the far North in Game of Thrones – the wolfswood scenes were shot in this woodland.
Nature & wildlife
The river’s ecology is shaped by its water chemistry. The Shimna is naturally nutrient-poor and acidic, and that suits a group of mosses and liverworts that are rare elsewhere in Northern Ireland: the ASSI listing singles out Portuguese feather-moss, Holt’s mouse-tail moss, compressed flapwort and the liverwort overleaf pellia, all clinging to the damp, shaded rock.
The banks are oak, beech, ash and birch, tangled with rhododendron and ivy. Otters work the lower river near the mouth, and kingfishers, grey wagtails, dippers and grey herons patrol the shallows. A feral Mandarin duck population has bred on the river since the 1970s, an odd splash of colour if you spot one.
Walking & exploration
Most people meet the Shimna on the marked trails of Tollymore, which are well signposted and range from flat riverside strolls to longer woodland loops.
- The River Trail follows the tree-lined banks upstream past the Hermitage to Parnell Bridge, where the water tumbles over the rocks. Mostly flat, and the best of the walks for families.
- The Arboretum Path skirts the park’s historic arboretum, running through mature broadleaf trees into experimental plots of monkey-puzzle and eucalyptus.
- Mountains & Drinns Trail is a longer loop across conifer and broadleaf woodland, crossing several of the historic bridges. The optional Drinns extension adds a moderate climb.
The one warning worth heeding: in spate the river rises quickly and the smooth rock at the water’s edge gets treacherous. The cascades are at their best after rain, but that is exactly when you keep children back from the bank and stay off the rocks.
Angling on the Shimna
The Shimna is well regarded for Atlantic salmon and sea trout, and the clear, fast water over a rocky bed makes it a genuine test. The Irish record sea trout – 16 lb 6 oz (7.43 kg) – was landed here in 1983 by Thomas McManus, and the river still gets strong runs.
A permit is required; day and week tickets are sold at the Newcastle Visitor Information Centre, 10–14 Central Promenade, Newcastle, BT33 0AA, or through the Shimna Angling Club. Check the current season dates before you travel, as they change. Wading is tricky in spate conditions, so ask at a Newcastle tackle shop about water levels and safe crossings before you commit.
Practical information
The river is free. Most visitors park at Tollymore Forest Park, which charges £5 per car, £2.50 per motorcycle, £13 per minibus and £35 per coach; it is free if you arrive on foot. The park is open daily from 10:00 until sunset and has toilets, baby-changing and picnic areas. Paths can be uneven or slippery after rain and several of the old bridges have steps, so wear proper footwear.
The park entrance sits just south of Newcastle off the A2 coast road. Translink Goldline buses stop in Newcastle, a short walk or taxi from the gate; Belfast International and George Best Belfast City are the nearest airports. For summer visits, come on a weekday morning – you get the early light through the canopy and miss the weekend crowds. Bring a waterproof whatever the forecast says; the Mournes make their own weather, and the river you came to see is the one that turns up after the rain.