When working with Geo locations you can choose either RelativeLocation or GeoLocation. The concept of RelativeLocation is that they are always relative to the current user location and this is why we prefer these when we need to test. GeoLocations are fixed to a certain latitude/longitude coordinate and stay at exact this place. In order to make sure that you have specified the correct coordinates when working with GeoLocations you can also advice these websites to Convert Lat and Long to Address and to Get Latitude and Longitude.
Also, take a look at distanceToUser function of AR.Location.
I am currently developing location-based AR application using wikitude sdk,
I am able to place markers/ images on pre-defined locations,
but the problem is the size of these markers are not changing according to distance.
I want small marker size for farthest location and big markers for closest location.
Please tell me how to achieve this.