I need to know about easement/right of use laws regarding real estate. Here's the reason I ask:

Our family owns property up north and owns the trail/road going back to it from the main paved road. There is a cabin further on down the trail, and my grandparents have allowed the owners to use the trail to get to their property. Nothing has been written allowing them, it's just understood between our family and the owners of the other cabin.

Now that cabin is up for sale. My family seems to think that the people are going to have a hard time selling it because any other owner will essentially not have a way back to their property. I seem to remember something about how if you allow someone to use your property for a certain time period, it becomes part of their land also. Anyone know anything about this?

Other questions need to be asked. Does the path end at this cabin? Is there any other permanent access? Your property is servient to theirs regardless of it being in writing or not. "It goes with the land" I would talk to an attorney to find case law.

Add to the above comment...If the access is not covered by case law (a prior), you may have the option of keeping the cabin landlocked and eventually purchase it yourselves to add to your estate or sell a deeded right-of-way to the new potential owners for a resonable fee.