The Hawaiian island of Ni'ihau, the Forbidden Island:
Ni'ihau is the smallest inhabited Hawaiian island. It is visible from the Leeward coast of Kaua'i, sitting about 17 miles to the SW. The island was sold by King Kamehameha to the Robinson family in 1863. The family has kept ownership of the island since that time, and has preserved the island for the native populace. Travel to the island was restricted in 1915 by Aubrey Robinson, which remains in effect to this day.
Significant reforestation efforts were performed in the early 1900's to increase the amount of water captured from the tradewinds. Since the island sits in Kaua'i's "rain shadow," the island is very dry.
Today the Coast Guard patrols the island to ensure that no landings are attempted. No one is permitted to visit without an invitation from someone on the island. The island lacked electricity until recently, when they started importing some solar power for limited usage. There is some trade and commerce with the other islands. Children from Ni'ihau take canoes to Kaua'i weekly to attend school. Many full time residents commute to Kaua'i for work, medical or social activities.
In 1987, hunting tours of the island were offered, which involve receiving an invitation from the tour operator who lives on the island. Helicopter tours over the island or boat tours off the coast are the only other ways to get close.
I knew a woman who had lived on the island for a time while she was a child. Her father worked for the Hawaiian government and had a job which required the family to live there. She told me a story about the island having just two trucks to move things around, on very poorly maintained roads. At some point the trucks ran into each other and were damaged. They didn't use the trucks much after that.