Erddig Hall is a National Trust property on the outskirts of Wrexham, Wales.
The building was sold to the master of the Chancery, John Meller in 1714. John Meller refurbished and enlarged the house (including adding two wings in the 1720s), and, on his death in 1733 unmarried and childless, passed it to his nephew, Simon Yorke (d. 1767) (first cousin of Philip Yorke, 1st Earl of Hardwicke). The house was passed down through the Yorke family until March 1973, when the last squire Philip Scott Yorke gave it to the National Trust. This followed the collapse several years earlier of a shaft from the nearby coal mine (Bersham colliery) under the house, causing subsidence of 5 feet (1.5 m), which seriously affected the structural security of the house to the extent that, without suitable underpinning, it would have become a ruin. It was strengthened using the compensation of £120,000 the National Trust was able to extract from the National Coal Board. 63 acres (25 ha) of Erddig Park (out of view of the house) was subsequently sold for £995,000 and this paid for the restoration work on the house. The restoration was completed on 27 June 1977 when Charles, Prince of Wales officially opened Erddig to the public, joking that it was the first time in his, albeit short, life that he had opened something that was already 300 years old.
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