It was decades ago when a local council, going on site to put up a new school on what had been allotments with sheds, found that the bulldozer had gone down a big hole. This was a mining district where coal had been taken even in the Middle Ages.
Monks from the local monastery, or perhaps lay employees or tenants had extracted coal from shallow bell shaped pits. Then there were no tunnels etc. just Bell pits dotted about all over the place, without much logic and long forgotten. They had been capped at some time in the past.
As well as these there were the remains of other workings, both for coal and other minerals where found. Again these were from another age and there were no records of them. The more extensive of these had an added problem because like modern mines a movement of rock etc. could be transmitted along any fault line.
Our ancestors had been very busy underground mining and digging for many reasons all over the place. I recall reading Harmsworth Magazines at Grandma's from the 1890's with articles about the long established salt mines of Cheshire causing local towns to become lop sided.
All these and nature too have endowed us with potential problems for now and the future and any of the shifts of activity or other causes can give us a nasty surprise or shock. Such as instead of fairies at the bottom of the garden a cavern opens up and the car insurance does not cover it.
The closure of the M2 because of a big hole, luckily in the central reservation, is said to be a Dene Hole, not a Sink Hole. The Vikings are blamed for it, because they were as busy as any others in digging for materials.
So you never know. Add to this the matter of the water table. In many urban areas at one time industry and related activities took out a great deal of the underground water.
As this industry has declined in many places the water table has been reinstating itself. The effects of this could be interesting and unpredictable. Be careful of basement flats or storing the family treasure in one.
Depending on what is underneath, how it relates to other strata and the geology there is a great deal of potential for events and issues in many place. Whether the insurance industry or government can make some sensible arrangements or cover is a real question, is it a Euro responsibility?
As we build more, reshape more and redirect nature more there are going to be a lot more issues, events and unexpected happenings. Don't bet on it, you may be on a loser.