It forms the southeastern corner of South Hamgyong's Tanchon and the western point of a narrow bay sheltering Songjin and Hwadae.

Yongdae Gap is the southern point of a small peninsula whose most conspicuous summit is Wonsandok San, which rises to an elevation of 504 meters (1,654 ft) about 4 miles (6.4 km) due north of the cape.

The highest visible mountain from the point is Yongyon San(용연-산, 龍淵山), which rises to an elevation of 1,598 meters (5,243 ft) about 17 miles (27 km) farther NNW.

[2] This has a depth of 9.1–13 meters (30–43 ft) and bottom in fine sand, but is unsafe except as a shelter from NE winds.

Yongdae Gap has a lighthouse, but it is closed to the public[4] and the American National Geospatial-Intelligence Agency notes that "the existence and operation of all navigational aids should be considered unreliable on the east coast of North Korea".