The western terminus of NH 104 is in Danbury at U.S. Route 4.

NH 104 is locally named the Ragged Mountain Highway between Danbury and Bristol.

Until the 1970s, NH 104 used the Smith River Road between Danbury and Bristol.

This scenic, winding road parallels the Smith River.

However it was a frustratingly slow drive as a main highway, so the new overland Ragged Mountain Highway was a welcome replacement route for NH 104, leaving the old Smith River Road as a popular route for recreational access to the river.