Fifty years ago one of the most controversial construction projects in modern Welsh history was opened when the Tryweryn valley reservoir was built to provide water for Liverpool.

Nearly 70 people lost their homes as a result when a whole village was cleared and flattened to make way for the new lake, an event that was named by locals as "the drowning".

At the time there were huge protests, including two bombings aimed at stopping the reservoir being built.

Hywel Griffith reports.