Code of Federal Regulations Title 43. Public Lands:  Interior § 43.423.11 What areas are closed to public use?

(a) Those that were closed to public use as of April 17, 2006, as evidenced by fencing, gates, barriers, locked doors, road closures, signage, posting of notices, or other reasonably obvious means, as provided in § 423.14;

(b) Those that are closed after April 17, 2006 under § 423.12;

(c) Those that are closed periodically and regularly under § 423.13;  and

(d) Those that are closed to off-road vehicle use pursuant to 43 CFR part 420.