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In page Highbury:

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John Dawes, a real estate developer,[citation needed] acquired the site of Jack Straw's Castle together with 247 acres (1.00 km2) of surrounding land. In 1781 he built Highbury House at a cost of £10,000 on the spot where Highbury Manor had stood. Over the next 30 years the house was extended by new owners, firstly Alexander Aubert and then John Bentley, to include a large observatory and lavish gardens.