The British government has announced plans for major improvements at Stonehenge to be completed ahead of the 2012 Olympics, when hordes of visitors are expected.

The hotly debated plans call for one of the roads near the prehistoric monument to be closed and grassed over to make the site more tranquil and to link the mysterious stone circle to the rest of the site. In addition, the antiquated visitor’s centre right next to the site will be shut down and replaced by a modern reception centre about 2.5 kilometres from the stones.

Visitors will be able to use the centre and then take a bus to the site, officials said. The plan is expected to cost about $44.3 million, officials said.

“This will lead to a pragmatic and affordable scheme which will make significant and vitally needed improvements to what we have now,” said Barry Cunliffe, chairman of English Heritage, which oversees the site and many other landmarks.

Stonehenge is a World Heritage Site that is one of the most visited monuments in Britain, but the visitor experience has long been hampered by the presence of two heavily travelled roads that go quite near the stone circle.

“Stonehenge is of international importance, but the setting for the monument is very inappropriate,” said Loraine Knowles, Stonehenge project director for English Heritage. “This will be a significant improvement.”

One of those roads will now be closed. Heritage planners had hoped to use a tunnel to take traffic on the other road away from the monument, but that expensive proposal has been rejected.

Knowles said Stonehenge will remain open to visitors while the construction work is done.