That sounds right, but how is "continuous" defined in the easement context? Daily? Once a week? Once a year? I don't know the answer, but the question illustrates the danger of the situation.

I like that website link from PaulC, but even it includes some potential pitfalls. It says that the time period for adverse possession in Virginia is 15 years, which is true if you are talking about the classic squatter's rights case where the squatter claims ownership of the land. The pitfall, however, is that I think that Virginia uses a different period - 20 years last time I checked - in cases involving the establishment of prescriptive easements (the term used when an easement is created by adverse use).

The law of adverse possession and prescriptive easements has interesting twists and turns, some of which seem counter-intuitive. For example, what would happen if you gave permission for these people to cross your property? Wouldn't that negate the requirement that the use be "hostile"?

I'm not offering answers to any of these questions. I offer them to illustrate how uncertain this area of the law can be.