Hatfield-McCoy Trails Deputy Executive Director John Fekete says all the system's blue trails have been opened to the small four-wheel vehicles. The blue trails are considered the more difficult ones.
Fekete says the system's green trails, which are the easiest, always have been open to UTVs.
With the expansion, Fekete says almost 80 percent of the 500-mile system is open to UTVs.
The trail system also is used by all-terrain vehicles and motorcycles.