Route 51 is a three mile (5 km) road that stretches from the junction Wapaa Road with Route 58

Hawaii Route 58

Route 58 is a two mile road that stretches from Route 50 in Lihue to the junction of Wapaa Road with Hawaii 51 near Nawiliwili Harbor on Kauai island.- Route description :...

 at the Nawiliwili Harbor in Lihue to Route 56

Hawaii Route 56

Route 56, also known as Kuhio Highway, is the main highway on the north and east shore of Kauaii island.-Route description :Route 56 runs , stretching from Hawaii Route 50 at the junction of Rice Street in Lihue, Hawaii to the junction of Hawaii Route 560 in Princeville on the island of Kauaii...

 north of Lihue on The Garden Isle

Kauai

Kauai or Kauai, known as Tauai in the ancient Kaua'i dialect, is geologically the oldest of the main Hawaiian Islands. With an area of , it is the fourth largest of the main islands in the Hawaiian archipelago, and the 21st largest island in the United States. Known also as the "Garden Isle",...

.

Route description

After the junction with Wapaa Road, Route 51 is signed with Rice Street for less than a mile. Route 51 then spilts off with Rice Street and becomes Kapule Highway where the final segment north of the airport was completed in 1988. The road intersects with Route 570

Hawaii Route 570

Route 570 is a one mile road that stretches from Route 56 in Lihue to Lihue Airport on the island of Kauai. Before of the construction of Route 51 in the 1980s, the road provided primary access to Lihue Airport with the north and eastern shores of the The Garden Isle.- Route description...

 near the Lihue Airport. Heading north towards the eastern and northern towns of Kauai, Route 51 ends at the intersection with Route 56.

Major intersections