© Global NewsSo far, no one can explain why these craters are suddenly appearing in Quebec City.
They began appearing last week - massive, mysterious craters on a hill in Quebec City.
"I've lived here 30 years, it's a mystery," said resident Edwin Richard.
About 40 sinkholes between five and eight meters wide began eating out a hill in the Charlebourg borough. They're so big, they've put nearby homes in danger. On Friday, experts were on hand to try to figure out what's causing the craters.
"We have a problem here, it's not possible to say the cause," said city engineer Marcilio Gama Coehlo.
"We spoke to specialists at the ministry and at the university - they have no idea," said city engineer Daniel Lessard.
The only thing they do know is that the hill used to be the site of a sand pit.
For now, the only thing they can do is more tests.
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