The Korean Peninsula is a peninsula in East Asia. It extends southwards for about 1,100 kilometres from the continental Asian mainland into the Pacific Ocean and is surrounded by the East Sea/Sea of Japan on the east, the East China Sea to the south, and the Yellow Sea to the west, the Korea Strait connecting the first two bodies of water. It is currently divided into the Republic of Korea in the south and the Democratic People's Republic of Korea in the north. The single term Korean Peninsula is therefore often used to refer to these two states at the same time. Up until the division of the peninsula following the end of World War II, Korea was a single political entity for many centuries whose territory roughly coincided with the Korean Peninsula.
The northern boundaries for the Korean Peninsula is commonly (and tacitly) taken to coincide with today's political borders between North Korea and her northern neighbours, China (1,416 km) and Russia (19 km). These borders are formed naturally by the rivers Yalu (Amnok) and Tumen (Tuman). Taking this definition, the Korean Peninsula has an area of approximately 220,000 km².
Mountains cover 70 percent of the Korean Peninsula and arable plains are generally small and far in between the successive mountain ranges. The peninsula becomes more mountainous towards the north and the east, with the highest mountains (including Paektu-san which stands at 2,744 m) found in the north.
The peninsula has 8,460 kilometres of coastline, and the south and west coasts are highly irregular in particular; most of the 3,579 islands off the peninsula are found along the south and the west coasts.
The Unification Flag has a blue map of the Korean Peninsula on a white background. The flag was introduced in 1991 to represent the joint North and South Korean team at the table tennis world championships. The athletes from the two Koreas marched together under this flag at the 2000 Sydney Olympics and the 2004 Athens Olympics.