During the late 1930s and early 1940s, land-based planes lacked sufficient flying range for Atlantic crossings. Foynes was the last port of call on its eastern shore for seaplanes. As a result, Foynes would became one of the biggest civilian airports in Europe during World War II. Surveying flights for flying boat operations were made by Charles Lindbergh in 1933 and a terminal was begun in 1935.
The first transatlantic proving flights were operated on July 5, 1937 with a Pan Am Sikorsky S-42 service from Botwood, Newfoundland and Labrador on the Bay of Exploits and a BOAC Short Empire service from Foynes with successful transits of twelve and fifteen-and-a-quarter hours respectively. Services to New York, Southampton, Montreal, Poole and Lisbon followed, the first non-stop New York service operating on June 22, 1942 in 25 hours 40 minutes.
All of this changed following the construction and opening in 1942 of Shannon Airport on flat bogland on the northern bank of the Estuary. Foynes flying-boat station closed in 1946. A college for the learning of the Irish language was opened in the former terminal in 1954. The Port Trustees purchased the building in 1980 and the Foynes Flying Boat Museum leased a portion in 1988.
One of Foynes's main claims to fame is the invention there of Irish Coffee. This came about, it is said, in order to alleviate the suffering of cold and wet passengers during its aviation days in the 1930s and early '40s. The Foynes Flying Boat Museum contains much memorabilia from that era, including the original radio and weather room, along with its equipment and a full-size replica Boeing 314 flying boat.