Overview
In October 1907 the first commercial wireless messages to cross the Atlantic were tapped out in Morse from this bog outside Clifden and answered from Glace Bay in Nova Scotia. What survives of Guglielmo Marconi’s station is a scatter of concrete foundations on Derrigimlagh Bog, free to walk at any hour, on the Wild Atlantic Way in Connemara.
If you only have half an hour, walk the surfaced loop that ties the Marconi site to the Alcock and Brown landing spot: two firsts in long-distance communication, a few hundred metres apart on the same stretch of peat. Before undersea cables were reliable, Marconi’s high-power spark system was the fastest way to get a message across the ocean, which turned this empty peatland into a working node of world news and shipping.
History and engineering
When Marconi went looking for a transmitter site in the early 1900s, he wanted open ocean to the west, cheap fuel for the generators, and little electrical interference. Derrigimlagh gave him all three, plus a limitless supply of peat to burn. The Marconi International Marine Communication Company turned the bog into an industrial complex.
- Power: Six peat-fired boilers drove generators producing 150 kW at 15,000 volts. The high-voltage sparks could be heard and seen for miles across the county.
- Aerials: Eight wooden masts, each 61 metres (200 ft) tall, held up 12 km of wire running east across the bog. Their concrete bases are still standing.
- Buildings: Separate blocks housed the condensers, transmitter, receiver, and staff quarters, all built to take the Atlantic weather.
On 17 October 1907 the station opened for commercial traffic. The first message – spelled out as ‘L-O-N-D-O-N’ – was picked up by the sister station at Glace Bay, and the duplex system let signals run in both directions at once, making Derrigimlagh a live link for commerce and diplomacy.
The station earned its keep in a crisis. In 1912 it relayed the first news of the Titanic disaster to Europe. It handled an early transatlantic voice transmission in 1919 and carried King George V’s address in 1924. Neutrality was no protection during the Civil War: republican forces attacked and damaged the station in July 1922. Shortwave technology eventually made the huge spark-gap plant obsolete, and the station closed in the late 1920s. The masts came down, and the bog took back the rest.
Walking the discovery trail
The interpretive loop covers roughly 1.5 km of marked track, and you can extend it along the bog paths toward the coast. It passes the main remnants of the complex.
- Interpretive panels: Boards at the key points cover the station’s construction, its part in maritime safety, and the engineering of early radio.
- Audio: QR codes along the trail link to recreations of the crackle of the 1907 inaugural transmission and the 1912 Titanic flash, so you can hear the history without a guide.
- Bog ecology: The path crosses active blanket bog. Look for heather, bog cotton, and sundew underfoot, and for curlew, redshank, and brown hares in the open ground.
- Viewpoints: From the raised bog the sightlines run clear across Ballinakill Bay and the Twelve Bens, with the Atlantic horizon to the west on a clear day.
Practical information
- Location: Derrigimlagh Bog, a short drive south of Clifden off the R341.
- Access: Turn off the R341 at the Derrigimlagh signpost and follow the marked gravel track to the discovery point. Free parking at the trailhead.
- Opening hours: Open year-round, 24 hours. The site is outdoors and unstaffed.
- Cost: Free.
- Facilities: No toilets or refreshments on-site; the nearest are in Clifden. Picnic benches at the trailhead.
- What to bring: Sturdy shoes or wellies – the bog turns soft and waterlogged fast. A charged phone for the QR audio, waterproofs, and a camera.
- Accessibility: Uneven, boggy terrain, not suitable for wheelchairs or pushchairs; best for able-bodied walkers and older children.
- Contact: Managed with the Clifden and Connemara Heritage Society and Fáilte Ireland. Enquiries to info@connemaraheritage.ie.
Nearby stops
- Alcock and Brown crash site – A few minutes east along the loop, this is where the first non-stop transatlantic flight ended in a bog landing in 1919. The wreck is long gone, but panels tell the story.
- Ballinakill Bay – A sheltered inlet with a small sandy beach and calm water, good for a post-walk picnic.
- Clifden – The self-styled capital of Connemara, with cafés, independent shops, and the ruins of Clifden Castle above the estuary.
For photographs, come in the late afternoon, when low sun rakes across the peat and throws the concrete mast bases into relief against the Atlantic.