I guess we can blame ourselves, as we were looking for the wormhole. We didn't realise the world would change if we went through it. Lost in time for a while, but managed to return back to our universe by going through the wormhole again.
Nokian Pirunpesänkivi (some 30 kilometres from Tampere) is a tafoni, a rock with holes through it as if they were made by worms. It is a wonder of nature that can be visited without any special equipment or knowledge. Just be careful about going through...
See also the articles at Retkipaikka about this and other tafonis in Finland.
Photos and videos (c) 2016 by Jari Arkko and Janne Arkko. This blog is also available at TGR. Tämä blogi löytyy myös suomeksi Relaasta.