These two photos show Tateno Gorge before and after government construction. If the gorge had been damaged by the earthquake that would have been one thing, but this seems to have been a human decision – one in which not even the government of Kumamoto Prefecture was consulted:
“The restoration work in the area includes the construction of a new bridge designed to replace the Great Aso Bridge that collapsed following the Kumamoto earthquake disaster in April 2016. The central government, however, did not inform the Kumamoto Prefectural Government that it would be tearing down the naturally formed columnar joints in the process. The vertical cracks, which were created after lava from nearby Mount Aso cooled down and solidified, are considered to be a geological phenomenon. The demolished cracks were discovered by a member of a citizens’ group on Aug. 30.”
– Kirk
http://mainichi.jp/english/articles/20170914/p2a/00m/0na/024000c