Japan’s Emperor Akihito formally abdicated on Tuesday, marking the first such occasion for 20 years in the world’s oldest monarchy.
The 85-year-old is to be replaced by his son Naruhito after he performed the abdication rituals at Tokyo’s Imperial Palace.
In final comments before stepping down, he said he would “pray for the peace and happiness of all the people in Japan and around the world”.
Akihito will technically remain emperor until the stroke of midnight when Naruhito takes over and the new era of "Reiwa" – meaning "beautiful harmony" – begins, lasting for as long as he reigns.
Earlier on Tuesday, draped in ornate golden-brown robes and wearing a towering black hat, Akihito reported his abdication to his ancestors and Shinto gods at several sanctuaries in the palace.
On Wednesday, the 59-year-old Naruhito will inherit the imperial regalia in a 10-minute ceremony that is off-limits to female royals, even his wife Masako. He will shortly afterwards make his first address to the nation as its 126th emperor.
Crowds were expected to gather to count down to the new era outside the palace and at the scramble crossing in Tokyo's lively Shibuya district, although the drizzle threatened to dampen some of the enthusiasm.
Security has been beefed up with extra police patrols on the streets, sniffer dogs scouring the palace grounds and even divers inspecting the moat.
A more public enthronement ceremony will take place on October 22, during which Naruhito will parade through the streets of the capital and be congratulated by other world leaders and royalty.
President Donald Trump sent congratulations, offering "heartfelt appreciation" to the outgoing imperial couple and stressing the "close relationship" between the US and Japan.
He will become the first foreign leader to meet the new emperor on a trip in May.
The abdication has resulted in a 10-day holiday in Japan, although polls show many famously hard-working Japanese were opposed to such a long break.
They have nonetheless taken the opportunity to travel, with bullet trains and airports overflowing and Tokyo's usually packed commuter trains eerily empty at rush hour.
Entrepreneurs have sold everything from "Reiwa" bottles of sake to $10 cans of air from the "Heisei" era of Akihito's reign.