Consult an attorney immediately. They cannot block a public access road. And if that is the only route to your property, they cannot prevent you from using it. The attorney will tell you what the laws are that apply in your state.

An access road is a road giving entry to another, usually larger, road, especially a motorway.

Landlocked land is land that has no access from a road except over the property belonging to others.

Landlocked land is land that has no access from a road except over the property belonging to others.

Landlocked land is land that has no access from a road except over the property belonging to others.

Landlocked land is land that has no access from a road except over the property belonging to others.

by road or river

By permission or invitation of the road's owner.