Yeonpyeong Island – claimed by North Korea and South Korea
Yeonpyeong Island lies on the South Korean side of the the Northern Limit Line (NLL) of the Yellow Sea, which serves as the maritime border between North and South Korea. North Korea rejects the NLL (and therefore the South Korean claim to the island) because it was designated unilaterally by the United Nations after North Korea and the UN failed to agree on a boundary. Yeonpyeong Island is eight miles from the North Korean mainland, but is claimed by South Korea.
Tensions over the island have occasionally escalated and fatal fire was traded twice in 2010 – once when North Korea unexpectedly shelled the island and another time when it torpedoed a South Korean naval vessel. Military drills by both countries in the area have raised international concerns.