Okutama Town is located at the northwesternmost tip of Tokyo and belongs to Nishitama District. It is one of the three towns in the Tama area. Covering an area of 225.63 square kilometers, it is the largest local government unit by area within Tokyo. The town is home to the man-made Lake Okutama (also known as the Ogouchi Reservoir), and its terrain is mostly mountainous and forested, making it the most rugged region in Tokyo. Known for its mountain tourism, it attracts a large number of hiking enthusiasts.
The annual average temperature in Okutama Town is around 11°C to 12°C, with a climate classified as Central Highland type. Winters are cold, with temperatures often more than 10°C lower than central Tokyo, and even colder than coastal cities in the Tohoku region such as Sendai and Sakata. It is the area within Tokyo that sees the most snowfall and snow accumulation. Snow on flat ground can reach up to 50 centimeters, and in some mountainous areas, it can exceed one meter. Due to its higher elevation, summer temperatures are relatively cool, with highs in August often below 30°C, making it one of the region's popular summer retreats.