One important thing that I haven't heard mentioned yet is that if a Libertarian system were implemented in a real country there would obviously be a period of transition where the state sold off all the public properties like roads etc. Most access problems would be solved during this period of transition as most people would try to purchase the formally public road leading to their property especially if a road only led to one's property. Alternatively, a group of property owners (those which are served by the road) could purchase the road and agree to allow anyone access to the road (or just owners, or owners and guests, or whatever the owners choose). Even in the unlikely circumstance that access was blocked because a property owner was in a coma during the transition period. When the property owner needed access they could trade something of value or even attempt to persuade the owners of potential access routes to give them access. Most of the fantasy land examples seem to assume that the property owner's blocking access value blocking access to the property more than anything else. That is highly unlikely. There are millions of neighborly disputes that are resolved without the government every year. Why assume that people would be unable to resolve disputes when there is a really small gov't or no gov't.

To the poster that said that political systems must address minor religious and social disagreements or devolve into tyranny. In my view any political system that meddles in religious or social disagreements (besides actual violations of rights) is a tyrannical political system.