Doc Central Otago manager Mike Tubbs said Doc charged the three men, who were riding trail bikes through the old Buster diggings north of Naseby, with interfering with historic resources on a conservation area without authority, entering a conservation area without authority and breaching a restriction.
The incident happened a year ago. The men had been offered diversion and would be making a donation to a Maniototo heritage project, Mr Tubbs said.
It had taken so long to deal with "as there were some other factors involved" and police had also been investigating.
The charges should act as a warning to others.
"This was taken very seriously and people must respect public land", Mr Tubbs said.
The men had ridden their trail bikes across a sluice face, leaving ruts which would speed up erosion.
"The diggings are of national significance. They are vulnerable to damage and we have fenced them off to protect them from vehicles."
Buster Diggings was one of the most distinctive man-made features of the 65,000ha conservation park, he said.
The diggings were worked seasonally from the discovery of gold in the 1860s through to the 1930s. They were at 1200m above sea level and were among the country's highest gold workings.
" ... the miners' extensive hydraulic sluicings of the quartz gravels resulting in a unique landscape, where huge areas of gravel have been washed away, leaving remnant pinnacles and outcrops rising out of the outwash plain," Doc says.
Mr Tubbs said the trail bike riders' actions were witnessed by a member of the public, who reported them to Doc.
Vehicle access was available through the tailings on a marked track, if people asked permission.
"We're coming right into the period when more people are using this park and we're just asking them to do it responsibly and enjoy themselves," he said.
