Hyde Park is one of the largest parks in London, and one of the Royal Parks of London. The Park is the largest of four parks which form a chain from the entrance of Kensington Palace through Kensington Gardens and Hyde Park, via Hyde Park Corner and Green Park (19 hectares), past the main entrance to Buckingham Palace and then on through Saint James's Park (23 hectares) to Horse Guards Parade in Whitehall. The park is divided in two by the Serpentine and the Long Water.
The park is contiguous with Kensington Gardens; although often still assumed to be part of Hyde Park, Kensington Gardens has been technically separate since 1728, when Queen Caroline made a division between the two. Hyde Park covers 142 hectares (350 acres) and Kensington Gardens covers 111 hectares (275 acres), giving an overall area of 253 hectares (625 acres), making the combined area larger than the Principality of Monaco (196 hectares or 480 acres), though smaller than the Bois de Boulogne in Paris (845 hectares, or 2090 acres), New York City's Central Park (341 hectares or 840 acres), and Dublin's Phoenix Park (707 hectares, or 1,750 acres). To the southeast, outside the park, is Hyde Park Corner. Although, during daylight, the two parks merge seamlessly into each other, Kensington Gardens closes at dusk but Hyde Park remains open throughout the year from 5 a.m. until midnight.
The park was the site of the Great Exhibition of 1851, for which the Crystal Palace was designed by Joseph Paxton. The park has become a traditional location for mass demonstrations. The Chartists, the Reform League, the Suffragettes, and the Stop the War Coalition have all held protests in the park. Many protesters on the Liberty and Livelihood March in 2002 started their march from Hyde Park. On 20 July 1982 in the Hyde Park and Regents Park bombings, two bombs linked to the Provisional Irish Republican Army caused the death of eight members of the Household Cavalry and the Royal Green Jackets and seven horses.