It was during my college days and the thing that had the most impact on us as students was the dreadful Aberfan disaster.
Gosh yes that was really upsetting
I had never heard of the Aberfan disaster and reading about it reminded me of the Vajont Dam disaster, 9 October 1963, which was caused by a landslide and killed nearly 2,000 people. The main cause was the lack of a proper geological survey and then ignoring early warning signs.
https://en.m.wikipedia.org/wiki/Vajont_Dam