For me, it’s has to be demolition & dismantling of railway infrastructure.
The absolute haste in removing any indication that there ever was a railway, back in the 60s & 70s is heartbreaking.
It almost comes across as rather spiteful.
An example would be the Southport to Preston railway, closed in 1964. Within weeks, stations, bridges & embankments had been completely removed. Ensuring there was no way of reinstatement in the future.
At least other countries had the gumption to mothball their closed lines..