On the French side, the first cable (laid in 1869) came ashore on a beach below the lighthouse at Le Minou on the north side of the entrance to the narrows leading from the open sea to Brest harbor. Starting in 1879, efforts were made to find a landing point further away from Brest. A small inlet at Deolen, 17 km west of Brest, proved ideal. Since then, all French trans-Atlantic cables have landed at Deolen. To avoid the long detour around Ouessant Island, extensions to Porthcurnow landed at Brignogan to the north.

At the end of the First World War, the German cable linking Emden, Fayal (in the Azores) and New York was assigned to France. This was rerouted to Deolen in 1920 and its operation entrusted to PQ. To give London access to three trans-Atlantic cables, a second extension was laid between Porthcurnow and Brignogan in 1918. In 1929, the Brest - Saint-Pierre - Cape Cod cable was damaged by a submarine earthquake south of the Newfoundland Grand Banks and had to be abandoned.

Until 1925, there was no terminal station as such at Deolen, just a small building some 200 meters above the landing point. Here the Submarine cables were joined to a buried landline running 17 km to the main post office in Brest. The building also contained measuring equipment to monitor the submarine cables and locate faults on the sea end.

In 1922, PQ decided to centralize submarine cable operations at Deolen. The new station, built on the site of the former cable hut, was commissioned in 1925. It was superbly situated.The Superintendent's house was on higher ground offering magnificent views over the Iroise Sea, the local name for the approaches to the narrows leading to Brest harbor.

In June 1940, the German army occupied Brest. The Brest - Cape Code, Brest - Fayal and Brest - Porthcurnow cables immediately ceased operation. The German forces did not, however, damage any of the submarine cables in the Brest area. Further out to sea, the British cut them and attempted to divert them to the British Isles for their own use. Throughout the German occupation of France, the German army exercised strict control to ensure that none of the cable equipment was used for clandestine activities. On the other hand, nothing was destroyed or removed. The Brest cable plant was placed under the control of a highly skilled German officer with specialist knowledge of underwater cables. Brest and Deolen were liberated on 3 September 1944 after a 40-day siege, including heavy shelling and bombing; but the cable station was intact and, thanks largely to the courage and efficiency of Superintendent Bernard, the Germans left without destroying this important resource. As a result, the station itself was ready to operate almost at once.

By 1945, the Brest - Fayal - New York link had resumed service after having been repaired by British cableships. To improve the connection with London, one of the Brignogan - Porthcurnow cables was rerouted to Deolen via a submarine extension in 1947.

The Deolen station remained operational until 1962 when the Brest - Fayal - New York cable was abandoned, after which, FCR sold the land and building. The equipment was removed and dispersed, most of it being destroyed. Fortunately, a few items were saved, including two Heurtley magnifiers. One of these is to be seen at the PleumeurBodou telecommunications museum in Brittany, the other is part of the historic telecommunications collection in Paris. Other surviving items are displayed by various organizations and at FCR's head office in central Paris.

It is a pity that Deolen in Brittany was not made into a museum similar to that at Orleans, Massachusetts.