In fairy stories, you will always find witches cottages in the middle of the woods, at a crossroads, or on a mountainside, places that are out of the way, but also, importantly, places you need to go close to in order to accomplish a task. They are always sited on the lonely route from A to B.
Magic always takes place on the borders of things: the threshold between life and death, coming and going, doorways, portals, mirrors…
So where might you find witches cottages if they existed today? The woods are full of picnic tables, the mountains are filled with skiers, and few of us still live the pastoral ways, yet have we not created our own woods out of our endless streets – the urban equivalent of the scary forest full of bad things that might waylay you?
They would have to be on or near somewhere we have to pass each day, most likely still the traditional crossroads, and also be sited at a border, a liminal space which is neither one thing or the other. And while unnoticeable except to trained eyes, passing them would be made difficult.
The fact is, they do still exist and one is sited quite close to where I live, near the viaduct at the point where the railway crosses New England Hill. This might explain the daily traffic snarl ups on this route and the constant train delays in and out of Brighton. I wouldn’t go so far as to say it is actually lived in, but it is inhabited. I know of several others around the city. Maybe there is one near where you live?