Wales' slate landscape could soon have the same global importance as the Great Wall of China and the Grand Canyon as it has officially been nominated for UNESCO World Heritage status.
If successful, the landscape running through Gwynedd will become the UK's 33rd UNESCO World Heritage Site and the fourth in Wales.
Pontcysyllte Aqueduct, Blaenavon Industrial Landscape and the Castles and Town Walls of King Edward in Gwynedd are the Welsh sites already boasting the prestigious status.
Slate has been quarried in north Wales for more than 1,800 years and was used to build parts of the Roman fort in Segontium in Caernarfon and Edward I's castle in Conwy.
Prime Minister Boris Johnson said the Government were "delighted" to submit the nomination as the area is one "of remarkable uniqueness and breathtaking beauty".
Boris Johnson said if successful, the status will only further the global reputation of the area.
Heritage minister Helen Whately announced she had submitted the formal nomination to UNESCO. She said: "The incredible slate landscape is hugely significant to north west Wales and its industrial heritage.
"The area is described as having 'roofed the 19th-century world' and the slate from the mines continues to have an influence on architecture around the world.
"This nomination is an excellent way to recognise the importance of Wales's slate mining heritage and will bring benefits not only to Gwynedd but the whole of north Wales by attracting visitors, boosting investment and creating jobs."
Gwynedd Council's cabinet member for economic development, Gareth Thomas, added that the importance of Welsh slate should have more international recognition.
The slate landscape in north west Wales became the world leader for the production and export of slate during the 18th century.
During the Industrial Revolution, demand for slate surged as cities across the UK expanded, with slate being widely used to roof workers' homes and factories.
By the 1890s, around 17,000 people were employed in the Welsh slate industry, mining 485,000 tonnes of slate a year and transforming the landscape.
Welsh slate is used on a number of buildings, terraces and palaces across the globe, including the National Assembly for Wales, the Royal Exhibition Building in Melbourne, Australia, and Copenhagen City Hall in Denmark.
The site in north Wales will now be considered by the International Council on Monuments and Sites over the next year before a final decision which is expected to be announced at the World Heritage Committee meeting in 2021.
Other Unesco World Heritage Sites in the UK include Liverpool's maritime waterfront, the Old and New Towns of Edinburgh, Stonehenge and the Tower of London.