Marshlands in Swanscombe have been granted special protected status, dealing a blow to plans for the multi-billion pound London Resort theme park due to be built there.
But conservationists have welcomed protection for a "wildlife haven" close to the M25 and on the Thames, which is home to a rare endangered species of jumping spider.
Swanscombe Peninsula in Kent has been designated a Site of Special Scientific Interest (SSSI) for its grassland, scrub, wetlands, grazing marsh and saltmarsh habitat which is home to an array of wildlife.
The peninsula on the Thames hosts more than 1,700 invertebrates, including the critically endangered distinguished jumping spider, breeding birds such as marsh harriers, reed warblers and bearded tits, and nationally rare plants.