Before answering that question, it’s best to understand a little bit about the Cleveland Ironstone formation and how it was mined. The ironstone seam isn’t an even, flat layer under the whole of Cleveland, you can think of it as a big bowl.
The edges of the bowl are at the surface, at these locations you can make horizontal ‘drift’ mines directly into the hillside, this is what happened at places like Eston and Guisborough.
The bottom of the bowl is deep underground, the lowest point is North Skelton where vertical shafts had to be sunk 740 ft to reach the ironstone.
The method of working underground is called Bord and Pillar, the bords being the tunnels where the ironstone has been removed and the pillars are left supporting the roof and land above.
If the pillars are later extracted, the roof collapses, this becomes known as ‘goafed’ and those areas can no longer be accessed.
So back to the original question, if you live Guisborough then 100% no, you are in a valley that has cut through the outer rim of the bowl. The ironstone is either side of you up in the hills to both the North and South.
If you live in Skelton then 100% yes, everywhere is either bord and pillar (the criss-cross pattern) or goafed (the dots)
Exactly the same is true of the vast majority of East Cleveland, through Brotton, Lingdale, Boosbeck and Loftus
Should you be worried ?
Absolutely not, just ask yourself would the miners have undermined their own homes and families sat above if they thought there was even the slightest risk ?
When subsidence did occur locally it was planned, like in the village of Upleatham where the landowner allowed the pillars underneath to be removed resulting in most of the original village and Upleatham Hall being lost.