In 1965, the small Welsh village of Capel Celyn was flooded to create Llyn Celyn, a reservoir supplying water to Liverpool. Despite strong opposition from 35 out of 36 Welsh Members of Parliament, the village—home to 67 people, twelve homes, a school, and a chapel—was submerged under more than 4 kilometers of water. The village was notable for being one of the last communities in Wales where Welsh was spoken exclusively in daily life. It wasn't until 2005, nearly 40 years later, that Liverpool City Council officially apologized for the decision. The push for the reservoir began in the 1950s, as Liverpool’s growing industrial needs required more water. The Liverpool Corporation, the city’s governing body at the time, targeted the Tryweryn valley in Merionethshire—now part of Gwynedd, north of the town of Bala. Rather than working with local Welsh authorities, the corporation pushed for a special law through the British Parliament: the Liverpool Corporation Act of 1957. This act allowed the city to bypass local negotiations and proceed with the project independently. The reservoir created by the project was vast—covering 320 hectares and holding nearly 71.2 million cubic meters of water. However, the method used to approve the project was controversial. Despite the opposition of nearly all Welsh MPs, the law was passed, highlighting the political imbalance between Wales and the central government in London. The village of Capel Celyn, with its modest but meaningful structures, was ultimately destroyed in the process. Of the 67 residents, 48 were displaced, forced to leave their homes and start over in unfamiliar places. The loss of Capel Celyn was not just a local tragedy but a symbol of cultural and political injustice. The Welsh language, already under pressure, lost one of its last fully Welsh-speaking communities. This event became a rallying point for Welsh identity, leading to the slogan "Cofiwch Dryweryn," meaning "Remember Tryweryn," which is still used today in political and cultural contexts. The Tryweryn affair had long-term political consequences. It is often seen as a key moment in the rise of modern Welsh nationalism, particularly for the Plaid Cymru party. The sense of betrayal by the central government—where a decision of such magnitude was made without regard for the views of Welsh representatives—helped fuel the movement for devolution. This process eventually led to the transfer of more powers from London to Cardiff, giving Wales greater autonomy in governance.