The contractor took possession last week of the site at Airman's Corner, 1.5 miles to the west of the Stones, to start construction of the new exhibition and visitor building out of sight of the stone circle.
In September, the Highways Agency will start work to upgrade Longbarrow Roundabout prior to the closure of the A344 in April 2013.
The £27m project, designed by Denton Corker Marshall, is financed almost entirely by Heritage Lottery Fund money, commercial income and philanthropic donations including significant gifts from the Garfield Weston Foundation, the Linbury Trust and the Wolfson Foundation. English Heritage needs just another £500k to see the project through.
The project, developed with the support of the National Trust, Wiltshire Council, the Highways Agency, and Natural England, will transform the setting of Stonehenge. The section of the A344 that currently runs past the monument - almost touching the Heel Stone - will be closed and grassed over, reuniting the stone circle with its ancient processional way and the surrounding landscape. The remaining part of the A344 will be closed to public vehicles, and will become the route of a new visitor shuttle service to the stones.
By summer 2014, the existing outdated facilities, car park, fences and clutter near the monument will be removed.
English Heritage chief executive Dr Simon Thurley said: "A new dawn at Stonehenge is truly upon us. Though the stones themselves have never failed to awe visitors their setting has been a national embarrassment and disgrace. After nearly 30 years English Heritage finally has a scheme that will transform the setting of the stones and our visitor's experience of them. The restoration of the landscape together with a major new exhibition on site will finally give our greatest and most famous monument the treatment it deserves.”