Area approximately 1,400ha of "Oji Forest - Sarufutsu" as for, Co., Ltd. Oji Paper of company-owned forest is, but, research education culture creation of place as walking trails etc. also have been maintained and developed, to the general public is open.

This whole area of wetland as for, approximately 6,000 years ago of Jomon period after of marine regression by formed relict lake and its surroundings which terrestrializing arose wetland area is.
Okhotsk Sea coastal area in most scale of large sphagnum moss community and Sakhalin spruce wetland forest which have developed, academic value which is high, valuable wetland is.