In 2002, new plans for a bored tunnel of 1.3 miles (2.1 km) were announced by the Secretary of State for Transport as part of a 7.7-mile (12.5 km) plan to upgrade the A303 to dual carriageway status, with the tunnel estimated to cost £183 million. This proposal brought further protests from the National Trust, English Heritage, UNESCO, CPRE, the Council for British Archaeology and local groups as the tunnel approach cutting would cut in two a prehistoric track way between Stonehenge and a nearby river. These groups are calling for a tunnel at least 2.9 km long, which would, while being sited within the world heritage site, clear most of the known major artefacts, claiming that if the government goes ahead with the 2.1 km tunnel there may never be another chance to remove the road from the site completely.