At midnight on April 30, thousands of people gathered in front of the Imperial Palace to celebrate the start of a new era.
One man had come with his son all the way from Kyoto for the occasion, describing it as a once-in-a-lifetime event.
Other people set their alarms to catch the literal dawning of an era. At Japan's easternmost point, Minamitorishima Island, local officials gathered on a beach to watch the first Reiwa sunrise.
Watch Video 1:41
Meiji shrine, dedicated to the great-great-grandfather of the new Emperor, attracted many worshippers. One said he was wishing for the success and health of his family. Another expressed hope that the new era will be a calm one.
Sumo wrestlers got together at their stadium in Tokyo to form the characters for "Reiwa."
Yokozuna Kakuryu said he hopes sumo will become more popular in the new era.
Watch Video 0:25
Some made sure the first day of Reiwa would be unforgettable. In a hotel in the northern city of Yamagata, five couples tied the knot at the stroke of midnight.
One of the brides says her parents had their wedding ceremony in the same hotel in the first year of the Heisei era three decades ago.
Other couples flocked to municipal offices across the country to file their marriage registrations on the first day of Reiwa.
For Chieko Sasaki in Fukushima Prefecture, the new era truly was a new start. She lives in the village of Iitate, near the crippled Fukushima Daiichi nuclear power plant.
Sasaki was forced to close her restaurant after the 2011 accident. On Wednesday she reopened it after an 8-year hiatus.
Sasaki said she thought she should restart her life on the first day of the new era. She marked the occasion by serving up local specialties for free.
For many people it felt like New Year's day, with lots of wishes for peace and happiness.