The method used by emergency services today have changed since my days, looking in the dark for a number of a house with a flashlight was the only way. The method used now can be downloaded onto a mobile phone, and is called* what3words* if you were unsure of exactly where you are you just have to tell the emergency service call handler, and they can trace you to within a meter, could be very useful in an emergency, especially in rural situations, or even if you are in a city and unsure where you are, i am quite amazed how accurate it is, just don't ask me how it works, kt