Tristan de Cunha: This British territory in the South Atlantic is reachable only by boat and is one of the most remote archipelagos in the world with 300 residents.
Socotra: An island in the Indian Ocean belonging to Yemen with pristine sandy lagoons and beaches. Reachable by fishing boat or two weekly flights.
The Darien Gap: A 125-mile strip of mountain, rain forest, rivers and marsh separating Panama and Colombia with no paved roads. Dugout canoes are a popular way of travel.
Laguna San Rafael National Park: A 6,726-square-mile national park that sits along the Pacific Ocean in southern Chile. Cruises are available, and the area is known for its mountain scenery and great fishing.
Mongolian Hinterland: The landlocked nation between Russia and China can be reached by a flight to the capital. Horseback riding and falconry are popular pastimes.
Auyuittuq National Park: The 8,300-square-mile park sits on Baffin Island, which is part of Canada's Nunavut territory. Visitors must take a boat in during the summer or a snowmobile in the winter. Access is impossible when ice is breaking up or freezing over.
Kamchatka Peninsula: The 182,356-square-mile peninsula of volcanoes, geysers, forest and wildlife sits in Russia's Far East between the Sea of Okhotsk and the North Pacific. Visitors can head north until the peninsula's only highway ends.
Papua New Guinea: Cell phone coverage is extremely limited in this South Pacific nation. Gorgeous beaches and marine life abound, but so do cannibals who haven't been seen or heard from in decades.