Cors Bodeilio National Nature Reserve, Anglesey

Internationally important wetland rich in wildlife

What's here

Dogs welcome
Parking (free)
Walking trail

Coronavirus update

Our sites and most visitor facilities are open.

We have changed the normal route for some of our trails to help you maintain social distancing – please follow signs on site.

Welcome

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

After East Anglia, Wales has the UK’s second largest expanse of fens.

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

It is an internationally important 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.

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.

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.

Anglesey Fens National Nature Reserves

Cors Erddreiniog

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 (the largest)
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

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

The reserve hums and rattles in spring and summer with the calls of breeding birds like reed and sedge warblers, reed buntings, grasshopper warblers, and stonechats – you can find 130 bird species here! You may also see lapwings and curlew, or even flush out a snipe.

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