North Koreans are joining in mass celebrations to mark the birthday of their leader, Kim Jong-il.
A week of festivities is scheduled, including exhibitions of Kimjongilia, a hybrid flower named after the leader, ice-skating, and music shows.
Pyongyang's streets are decorated with lanterns and goodwill messages, state media reported.
The official line is that this is Mr Kim's 69th birthday; however, records show he was born a year earlier.
The official story is that Kim Jong-il was born on a mountain that for centuries Koreans have considered sacred and the place of their ancestral origin.
This plays very much to the cult of the personality in North Korea, says the BBC's Nick Ravenscroft in Seoul.
But our correspondent says records in Russia show Mr Kim was actually born a year earlier in the former Soviet Union, where his father was leading a military brigade - making this his 70th birthday.
"The whole country is pervaded with great pride and joy," the official news agency reported on the eve of Mr Kim's birthday.
Gifts have been distributed as part of the celebrations, including sweets, chewing gum and biscuits for children, state media reported.
But some reports say the celebrations this year are lower key, partly because of acute food shortages in the North.
Two UN agencies have begun a mission to North Korea to assess the situation after a harsh winter, a sharp rise in global food prices, and continued international sanctions.
But the restrained celebrations are also aimed at making next year's events look even bigger by comparison - then, according to the authorities in Pyongyang, Kim Jong-il will be a septuagenarian, officially.
Also 2012 will be the centenary of the birth of North Korea's revolutionary founder - Kim Jong-il's father.
The country has long promised its impoverished people that 2012 will be the year it emerges as a strong and prosperous nation, our correspondent says.
Mr Kim is in poor health after a reported stroke in 2008.
Kim Jong-un, the youngest son of the leader Kim Jong-il, has been chosen as the future leader of this closed and secretive state.