Cors Bodeilio National Nature Reserve, Anglesey

Welcome

Cors Bordeilio is an internationally important wetland rich in wildlife.

Despite its name (cors means bog in Welsh), Cors Bordeilo is in fact a fen.

Follow our waymarked walks over the boardwalk out into the fen for great views and the chance to spot some of the wildlife and the wildflower display in spring and summer.

Cors Bodeilio is a nature reserve due to its unique mire (a wetland area without forest cover dominated by living, peat-forming plants). Mineral-rich water from the surrounding limestone drains into the wetland creating the perfect conditions for a whole host of rare plants, animals and wetland birds.

It is one of the three fens on Anglesey that have been designated as National Nature Reserves.

Walking trails

The walking trails are waymarked from start to finish.

Look out for the information panel at the start of the trails.

Find out about walking trail grades.

Fen Walk

• Grade: Accessible
• Distance: ¾ mile/1.2 kilometres (out and back)
• Time: 30 minutes
• Climb: flat
• Trail information: Follow the blue waymarkers along the flat 1.4 metre-wide boardwalk, stopping to take in the views out across the reedbed and fens. There are resting benches every 300 metres. Return to the car park by the same route.

Enjoy the sight and sound of wetland birds in the reed bed.

There's always something to see or hear, no matter what time of year.

Fen and Meadow Trail

• Grade: Easy
• Distance: 1½ miles/2.3 kilometres (out and back)
• Time: 1 hour
• Climb: flat
• Trail information: Follow the green waymarkers along the boardwalk with views across the fens, before following the unsurfaced trail to the meadows beyond. This section can become very muddy after wet weather. There are several benches where you can rest and take in the views. Return by the same route. Please note that horses may be grazing on the reserve.

Enjoy the wildflower display in the meadows in spring and summer.

What to see at the National Nature Reserve

The diverse plant life at Cors Bordeilio supports a range of insects, which in turn attract large numbers of wetland birds.

Outstanding for orchids and other rarities

The fly orchid takes the prize here. It’s an extremely rare orchid in Wales – with an even rarer yellow form found here.

There are eight other orchids here including the narrow-leaved marsh orchid, marsh fragrant orchid, common twayblade, and marsh helleborine.

Typical fen species include the great fen sedge and bottle sedge.

Other wetland plants thrive here such as black bog rush, sweet gale and blunt flowered rush.

Fantastic fen for minibeasts

The star has to be the rare medicinal leech – the only British leech with teeth that can bite through human skin.

There are also rare flies, water beetles, moths and 19 species of butterflies.

Easiest of all to spot are the numerous dragonflies and damselflies that hover and dart across the open water.

Reedbeds great for birds

You can find 130 bird species here!

The reserve hums and rattles in spring and summer with the calls of breeding birds like:

• reed and sedge warblers
• reed buntings
• grasshopper warblers
• stonechats

You may also see lapwings and curlew, or even flush out a snipe.

National Nature Reserve

National Nature Reserves are places with some of the very finest examples of wildlife habitats and geological features.

There are over 70 National Nature Reserves in Wales.

Three of the fens on Anglesey have been designated as National Nature Reserves:

• Cors Erddreiniog
• Cors Bodeilio
• Cors Goch (managed by the North Wales Wildlife Trust)

Find out more about National Nature Reserves

Find out more about the Anglesey and Llŷn Fens LIFE Project Wildlife highlights

Closures and diversions

Sometimes we need to close or divert trails for your safety whilst we undertake maintenance work

Occasionally we may have to close a site in extreme weather, such as high winds or snow and ice due to the risk of injury to visitors or staff

Please always follow any instructions onsite and make sure you follow any temporary diversion signs in place

How to get here

Location

Cors Bodeilio is 11 miles north west of Bangor. 

It is in the county of Anglesey.

Ordnance Survey map

Cors Bodeilio is on Ordnance Survey (OS) map 263.

The OS grid reference is SH 506 773.

Directions

Take the A4087 from Bangor, continue to join the A55 heading towards Holyhead, going over the Britannia Bridge and onto Anglesey.

Leave the A55 at junction 8, taking the A5025.

Turn right at the end of the slip road, following signs towards Benllech. Continue for 5 miles until reaching Pentraeth.

In the village, turn left at the traffic lights, signposted to Llangefni.

Take the first left towards the school and follow this narrowing road for 1¼ miles and the car park is on your right.

Public transport

The nearest train station is in Bangor or Llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch (which is a request stop).

For details of public transport visit the Traveline Cymru website.

Parking

Car parking is free of charge.

Overnight parking is not permitted.

Contact details

There are no staff at this location.

Contact our customer team for general enquiries during office hours, Monday to Friday.