The Cadw owned sites, along with other iconic landmarks such as the Wales Millennium Centre and the Senedd, will turn off their lights between 8.30-9.30pm, as part of a worldwide initiative to raise awareness of environmental and sustainability issues.
Last year a record 1.8 billion people across 138 countries took part, including thousands of people from Wales, and Cadw is once again encouraging people to join the initiative by signing up and switching off.
Huw Lewis, Minister for Housing Regeneration and Housing said,
“From Wales’s coastal and maritime heritage to ancient buildings and sites, it’s vital that as a nation we work towards a greener environment to safeguard our country’s diverse and unique heritage for future generations to explore.
“The Earth Hour blackout of these iconic buildings provides a poignant picture of how Wales could look if we don’t consider our natural environment.”
John Griffiths, Minister for Environment and Sustainable Development, said,
"The Welsh Government is committed to tackling the challenges presented by climate change and is pleased to support Earth Hour. Lights will be turned off at many major sites across our estate and we are encouraging other public sector bodies in Wales to do the same.
“I urge people across Wales to join hundreds of millions of people around the world in switching off non-essential lights on Saturday evening. This is your chance to make a contribution, however small, to a world-wide event which highlights concerns about our planet's future."