Lamps, lanterns, bonfires and fireworks: many cultures mark the dark with light.
Homes are lit with oil lamps and decorated with rangoli. The festival celebrates the triumph of light over darkness and is observed by Hindus, Jains, Sikhs and some Buddhists.
Thousands of paper lanterns are released into the sky, and people float small decorated baskets on rivers to let go of bad luck.
Visitors write wishes on paper lanterns and release them into the night sky above the old railway town of Pingxi.
Millions of clay lamps are lit along the ghats of the Ganga, with evening aarti ceremonies and boat rides.
Participants dressed as Vikings carry torches in a procession and set fire to a replica longship, celebrating Shetland's Norse heritage.
Swedes raise a decorated maypole, dance in rings and eat herring and new potatoes outdoors on the longest days of the year.
Families clean graves and light lanterns to welcome the spirits of ancestors. Kyoto ends the season with the Gozan no Okuribi bonfires on the hills.
People hang paper wishes on bamboo branches in memory of a legend of two star-lovers. Sendai's August celebration is one of the best known.
People gather around bonfires to sing and dance, and offer sesame, jaggery and popcorn to the flames in thanks for the winter crop.