Geo Targetly lets you create a 'zone' target which is done by specifying a latitude-longitude coordinate and a radius.

You can create multiple zones within a location segment and the minimum radius that can be targeted is 50 kilometers (or 31 miles) due to the location accuracy of IP geolocation. It won't work if you pick a radius below 50km, we don't recommend the use for small distances.

Zone targeting is useful when you want to target visitors a particular distance from a coordinate point.