Kensington Gardens, once part of the private gardens of Kensington Palace, are now among the Royal Parks of London and largely open to the public. The gardens are shared by the City of Westminster and the Royal Borough of Kensington and Chelsea and sit immediately to the west of Hyde Park, in west London. The gardens cover an area of 107 hectares (265 acres). The open spaces of Kensington Gardens, Hyde Park, Green Park, and St. James's Park together form an almost continuous "green lung" in the heart of London. Kensington Gardens are Grade I listed on the Register of Historic Parks and Gardens.