Nikko (日光, Nikkō) is a small town in Tochigi Prefecture that is known for being a gateway to Nikko National Park (日光国立公園, Nikkō Kokuritsu Kōen). It is also the home of one of Japan’s most famous shrines: Nikko Toshogu Shrine where Tokugawa Ieyasu rests.
Nikko National Park is an expanse of forest, mountains, waterfalls, and hiking trails that covers an area over 1,000 square kilometers and covers four prefectures, but the most visited areas are Nikko (the town and its surroundings) and Okunikko (the area to the west of the town near Lake Chuzenji).
The region is particularly popular in autumn when the leaves change color. In the Nikko and Okunikko area, this begins in late September around Ryuzu Waterfall and lasts until early November nearer Nikko town, but October is typically regarded as the best month to visit and so those planning on travelling to Nikko during this time are advised to book ahead.