Generally speaking, central Nikko is recognized as Nikko while area of Lake Chuzenji, around Mt. Nantai and Yumoto are called Oku-Nikko (Inner Nikko), but some people call it just Yumoto area. Border between Nikko and Oku-Nikko is Byoubuiwa rocky screen on the Irohazaka winding road.

There are some stories regarding name of Futara.
Mt. Nantai is also called Mt. Futara, and the name of Futara is derived from Potalaka in Sanskrit. Also, Futara can be divided into two Japanese words. One is futa, which means two in Japanese, and another word is ara, which means storm. The meaning of combination of those two words are two storms. According to a legend, god of wind and god of thunder appear at Byoubuiwa rocky screen and bring the two storms a year. Moreover, Futara can be pronounced Nikoh in another way of reading. You can imagine that the Nikoh became Nikko later.

Landscape of Oku-Nikko has been created dramatically by natural environment like an eruption. Lake, waterfall, grassy plain and marshland are gathered like a miniature garden. Nature has been remained its natural appearance since Oku-Nikko was designated as a National Park in 1934.

History of Oku-Nikko began when Priest Shoto succeeded to climb the Mt. Nantai in Nara-Heian period. Nikko developed as a training area for ascetics until Edo period, and developed as a resort area from Meiji era.

Weather of Oku-Nikko is relatively cold, but it is comfortable to spend the summer. Plants change their appearances in every season. You should bring chain for your tires when you come to Nikko by the car from December to March. Snow will not be heavy, but surface of the road will possibly be frozen.