CALEDON, Ont. -- The Cheltenham Badlands northwest of Toronto will be closed to visitors likely for several years starting at the end of this month while a long-term conservation plan for the ecologically sensitive site is developed, says the Ontario Heritage Trust.

The seven-hectare landscape of hummocks and gullies -- considered one of the best examples of badland topography in Ontario -- draws thousands of visitors annually, a number that has risen in recent years, said Catrina Colme, spokesperson for the trust, which owns the site.

"The increasing number of visitors has been causing accelerating erosion, and the closure is a protective measure to stop further damage," Colme said.

Over the years numerous signs asking people to stay off the badlands have been vandalized or removed, Colme said.

The large number of visitors' cars parked on the shoulder of Olde Baseline Road, which skirts the badlands, has also raised safety concerns, she said.

"Safety along that road is another big factor, so closing off access will hopefully discourage people from stopping."

A fence will be erected along the road to keep people off the badlands, an hour's drive from downtown Toronto.

An environmental consultant will begin work on the conservation plan this summer.

Removal of vegetation during land clearing and livestock grazing in the early 1900s led to erosion of the red shale bedrock, producing the badlands' distinctive appearance.