Inatori Hosono Kogen, Higashiizu

Inatori Hosono Kogen is a vast highland plateau spanning approximately 125 hectares at an elevation of 400 to 700 meters in the mountains of eastern Izu Peninsula, Shizuoka Prefecture. The plateau was formed around 200,000 years ago on the old volcanic slopes of Mount Amagiyama, and its volcanic origins have created a unique landscape that supports diverse flora and fauna. The site is seven times larger than the more famous Hakone Sengokuhara grassland, making it one of Japan's most expansive pampas grass viewing areas.

The highland's natural significance lies in its ecological features. Poor drainage in some areas created marshlands, including four distinct marshes: Nakayama Marsh No.1, Nakayama Marsh No.2, Shibahara Marsh, and Momono Marsh, all designated as natural monuments by Shizuoka Prefecture. These protected wetlands harbor rare plant species and must be viewed from designated walking paths only. The plateau offers spectacular 360-degree panoramic views of Sagami Bay, the Izu Islands, and surrounding peaks including Mount Amagi, creating a distinctive landscape where grasslands meet the sea.

Visitors come primarily for the seasonal displays of Japanese pampas grass that transforms the entire plateau into golden waves each autumn. The annual Pampas Grass Festival typically runs from early October through November and features guided nature walks, stamp rallies, music performances, and food vendors. The festival has been running for over a decade and includes a photo competition with monetary prizes. Beyond autumn, spring attracts visitors for mountain vegetable foraging, particularly bracken and osmund, while the plateau also serves as a popular paragliding destination year-round with tandem flight experiences available for beginners.

The site is located approximately 10 minutes by taxi from Izu-Inatori Station on the Izu Kyūkō Line, though having a rental car is recommended for flexibility. During festival periods, shuttle buses operate between the station and the plateau. Parking facilities include Hosono Kogen No. 1 Parking Area with 41 spaces and Hosono Kogen No. 2 Parking Area with 103 spaces. Festival admission is ¥500 for adults (junior high school age and above), with free entry for elementary school children and younger.