Dokdo is the easternmost territory of Korea and situated 87.4km to the southeast of Ulleungdo Island and 216.8km to the east of Jukbeon of the East Coast.
As it is 157.5km to the northwest of Oki Island of Shimane Prefecture of Japan, Japan cannot see Dokdo from Oki Island when we can see Dokdo from Ulleungdo Island on a clear day.
Dokdo has been created by volcanic activities.
It is not one island, but consists of two large islands Dongdo and Seodo and 89 small islands around them.
Dokdo's coordinates are 131?52'10.4" East Longitude and 37?14'26.8" North Latitude for Dongdo and 131?5'54.6" East Longitude and 37?14'30.6" North Latitude for Seodo.

You can see more about Dokdo here : http://en.dokdo.go.kr/pages/main/