Area code 859 split off of this area code in 1999. In an unusual move associated with area code splits in North America, it was decided to keep 606 in the more rural sections rather than in the urban parts. This was due to the fact the eastern and southern regions of the original 606 are notoriously poor, and it would be in their best interests to not have to go through the hassle and costs of implementing a new code there.
