Root cellars used to be on most homesteads both here in the USA and also across the pond. If you are growing or making food that can benefit from dark, cold conditions having a cellar can be the most useful square footage you have.
A root cellar can help ensure you get months of stable storage from items you grew or made. Fruits, vegetables, cheese and many other items can be stored underground in your cellar for later consumption.
I have never owned my own cellar but have seen and eaten foods from other folks who maintained a cellar. A few years ago we lived in an old farmhouse that was built in 1891, it had terrible or no insulation. There was a room that had been added on in the 70’s that served as the laundry room, it had two windows plus a poorly hung exterior glass door. The floor was tile on a slab of concrete. It would be 40-50 in that room for months in the winter. There was no heat in the room unless we used a space heater.
I used to store apples, potatoes and winter squash for months on end. I grew several hundred pounds of fingerling potatoes that stored perfectly. It was terrific buying bushels of local apples in late november that kept perfect until the end of February….or until we finished them off!
I also looked at a very old homestead in the mountains of Tennessee that had a cold storage room built into the ground that had a spring run. The room stayed very cold and dark all year long, but from late october until April it stayed at the perfect cellaring temperature. One reason it stayed so nice down there was the spring run, essentially a long concrete sluiceway that was about 8 inches deep with 50 degree spring water that came into the house via a pipe that led from a year round deep spring.
The owner told me the house was a dairy for many decades and the generations before used to place glass jars of milk in the spring run and they would keep for weeks. Of course it was raw milk that had many protective enzymes to help it stay fresher longer then any pasteurized milk. The jars would be in the water and it was gently running past and draining thru a spillway outside the house and into a small stream, very neat set up.
If I were to find mountain property that had some hills and a spring…I would certainly try to duplicate this ingenious system. Boxes of vegetables and even farmstead cheese used to stored next to the spring run. There was even a canning kitchen in the adjoining room. Really neat. Unfortunately the house was in a boxed canyon and had ZERO internet or phone. The mountain holler this house was in reminded me of a scene from The Deliverance, the place was not for me!! The kind of place when people get divorced they are still brother and sister! NUFF said.
So in closing, build a root cellar if you can! Here are some useful links for you.