This is an address field so give as much information as you can, and if names make sure you enter country as well so if you have the full address enter it as follows Buckingham palace London UK or GU32 1HT etc if you have a postcode or zipcode. Try and be as precise as you reasonably can. You can also give exact or nearest known lat,long codes as set out below...it is optional as location is not always relevant...

Approximate Latitutde if you have it and dont have the address.

optional lonitude measurement

This works similar to media library settings just a bit quicker and less screens to access.

optional additional editors notes...