Some background for context:
I was out on a bike ride in Loudoun County, Virginia last weekend, following a GPS route I got from a local bike shop. While traveling down a gravel road, a local motorist rolled up on me to tell me (somewhat menacingly) that I was on a private road and needed to turn around. Even though it was a through road, and I was about equidistant from either end, I politely thanked him for letting me know and turned around to follow him back to the main road (I lived in Montana long enough to learn not to piss off oversized-pickup-truck-driving locals).
I hadn't noticed it on the way in, but there was a small sign attached to the road-sign post reading, "Private road, not publicly maintained." It was small, close to the ground, and almost obscured by some tall grass. Very easy to miss by someone looking up at a road sign. If there is any chance that riding on such private roads could lead to a trespassing charge, I'd like to know so I can be more careful to avoid them when planning future routes (though I haven't found a way to distinguish them on a map or GPS yet).
I've found a few generic but contradictory definitions about what constitutes a private road and whether or not they are generally open for public use, but it seems like laws may vary quite a bit between states and especially in other countries. So, I'm really here in search of information relevant to Virginia roads in particular. Specifically, is there a default status regarding public travel on private Virginia roads? If so, what measures (if any) are necessary and sufficient to inform and/or restrict access for public road users? And could someone be charged/convicted for trespassing by traveling on such a road without permission?
I've found some related definitions on the state (commonwealth?) website, but nothing that seems to cover this situation specifically. For example, the term "Private Road Open to Public Travel" comes up in a lot of Virginia highway statutes, with the following definition pulled from a Virginia DOT manual on traffic control devices, which matches the definition given by the US Federal Highway Administration.
Private Road Open to Public Travel—private toll roads and roads (including any adjacent sidewalks that generally run parallel to the road) within shopping centers, airports, sports arenas, and other similar business and/or recreation facilities that are privately owned, but where the public is allowed to travel without access restrictions. Roads within private gated properties (except for gated toll roads) where access is restricted at all times, parking areas, driving aisles within parking areas, and private grade crossings shall not be included in this definition.
Since none of the examples provided match my situation of a private country road, I'm guessing this definition might not apply. But to me, the highlighted section seems to imply that a private road must be on a gated property or otherwise have access restricted at all times to be excluded as a "Private Road Open to Public Travel." Couldn't find a legal definition for "access restriction" anywhere, but I suppose a small sign near ground could be an attempt at restriction?
I will admit that after detouring a few miles to get back to my planned route, I ended up riding many miles on several different private roads that day. Most of them had much more prominently displayed and explicitly worded signage, including phrases like "no public entry" or "no through traffic" which I repeatedly ignored. What's interesting to me is that some of those private roads had businesses on them (I guess you're not through-traffic if you stop to have beer), and all of them were through roads connecting well-traveled public routes.