Overview
Walking or cycling into Castlewellan Forest Park is free; it’s parking a car that costs £5. The park runs to 450 hectares of woodland, lake and gardens under the Mourne Mountains in south-east County Down, managed since April 2022 by Newry, Mourne and Down District Council. If you only do one thing here, make it the Peace Maze. Beyond that, it’s a flexible day out: a champion-tree arboretum, 27km of mountain-bike trails, a lakeside castle and easy circular walks, with the town itself just up the hill.
The town and its ancient neighbours
Castlewellan’s layout is unusual for Ireland. Designed in the 19th century for the Annesley family, the town is built around two broad, tree-lined squares; the upper square keeps the 1764 Old Market House, now the library, while the lower is shaded by mature chestnuts that blossom in spring.
The hillsides around it are older still. The Drumena Cashel, off the A25, is an Early Christian stone enclosure with an Iron Age souterrain you can crawl into, and the Legannany and Goward dolmens mark Neolithic burials nearby, Goward’s granite capstone still balanced after several thousand years.
Forest park, arboretum and castle
The arboretum is the park’s quiet showpiece. Begun in the 1850s, with rare conifers and maples brought back from Japan, it holds many of the tallest trees of their kind in the British Isles and at least thirty champion specimens. Look for the giant sequoia grown from seed collected in California in 1856, and the ‘Castlewellan Gold’ Leyland Cypress, a golden mutant raised here in the early 1960s and propagated worldwide since. One caveat: the walled garden is closed until further notice as part of the restoration work below, so don’t build a visit around it.
Overlooking the water stands Castlewellan Castle, built 1856–58 to designs by the Scottish architect William Burn: local granite, Scottish-baronial towers and turrets, stone-mullioned windows. It became a Christian conference centre in 1974 and stays in private use, so it’s an exterior-only affair, best seen from the lakeside promenade where its reflection shifts with the light.
Next to the arboretum is the Peace Maze, one of the world’s largest permanent hedge mazes: 2.7 acres and 3,147m of paths through some 6,000 yews, planted in 2000 with community involvement and designed by Beverley Lear from ideas sent in by children. Most people solve it in about 40 minutes and ring the peace bell at the centre.
A £5.5 million National Lottery Heritage Fund project, ‘Re-rooting our past in the future’, is restoring the arboretum, walled garden and Grange Courtyard, with a new visitor centre and café due in summer 2026. In the meantime expect some construction hoarding, and restoration noise between 7.30am and 6pm on working days.
Walking, cycling and the lake
The park has 7.5 miles (12 km) of marked walking routes and 27 km of mountain-bike trails. For most visitors the pick is the Lakeside Walk, a flat 3.9 km loop around the water with steady views of Slievenaslat and the castle, and it’s fully wheelchair-friendly. Longer walking routes include the Slievenaslat (2.7 miles), Moorish Tower (3.2 miles), Annesley Garden (2.2 miles) and Cypress Pond (3.1 miles) loops. On the bikes, the longest waymarked trail is the Blue Lagoon at 1.0 mile; the black-graded Dolly’s Chute is closed at present after storm damage, so check trail status before you set off.
On the water, canoeing and paddleboarding run in the warmer months, and fishing needs a permit from the Forest Service office. Bike hire, kayaks and paddleboards come from the Life Adventure Centre at the park entrance.
Can you swim in Castlewellan lake?
No. Swimming in the lake isn’t allowed unless it’s a council-approved event, so the water here is for canoes and paddleboards rather than swimmers. In 2026 the lake was also one of more than 75 locations across Northern Ireland where the NI Environment Agency confirmed toxic blue-green algae, and a local triathlon group cancelled the swim leg of its event as a result. Check current notices before letting a dog into the water: algae is dangerous to dogs.
For the wider picture on which lakes north and south are open, monitored or closed, see swimming in Ireland’s lakes. The nearest recognised wild swim is Blue Lough in the Mournes.
Families and access
The ‘Animal Wood’ play area beside the Peace Maze is aimed at children roughly four to eleven: a short woodland path past sculpted badgers, red squirrels and a giant spider, and a big wooden play structure modelled on the Moorish Tower, with a climbing wall, fireman’s pole, rope bridge and a hollow-tree-stump slide.
Dogs are welcome through most of the park but must be kept under control, and are not allowed in the Play Park or the Peace Maze. The main routes suit limited mobility: mobility scooters manage the principal paths, a manual wheelchair can cover roughly six miles including the maze and gardens, and the Lakeside Walk is fully accessible. Near the main car park you’ll find accessible toilets, baby-changing, picnic tables and barbecue areas.
Practical information
- Opening hours: March & October 9am–6pm; April & September 9am–8pm; May–August 9am–9pm; November–February 9am–5pm. Closed Christmas Day.
- Admission and parking: Free on foot or bike; car parking £5 per ticket. Season permits are £25 (single park) or £60 (all parks) for frequent visitors.
- Getting there: Castlewellan is on the A25, about 32 km (20 miles) east of Newry and 6 km (4 miles) north of Newcastle, with regular Ulsterbus services to Newry, Newcastle and Belfast. The town’s railway station closed back in 1955, so there’s no train.
- Camping: Castlewellan Caravan Park takes camping and touring pitches, bookable online through the Visit Mourne tourism site.
- When to go: Trails turn muddy after rain, so bring waterproof boots for the hillier routes, and tackle the maze in the morning or late afternoon to dodge the midday crowds.
Events
The Soma Festival, running since 2013, brings live music, wellbeing workshops and family activities to the town, and the lake hosts the Queen’s Regatta. The Celtic Fusion international music festival ran here from 2002 for several years. Check local listings closer to your dates.
If you’re travelling light, park free in the town’s Lower or Upper Square and walk in: it’s only a few minutes down to the lake, and it saves you the £5.