I and my family really enjoy geocaching. Its a great way of getting to know an area, whether you local area or a place you're visiting. For example, the first couple of weeks of geocaching tought us that we live with a mile of a watering hole (Not an inn, but a pond!) used by travellers on the old Cambridge to Oxford "Porters Way", and a couple of miles in the other direction there are the remains of a mott & bailey castle.
There is a geocaching add-on for Google Earth that can make finding caches in a given area easier.
I use the same username on geocaching.com.
Give it a try, its as near to free as you can get these days.
Dave