Buddhists around the world have celebrated Vesak, one of the most important days in the Buddhist calendar. Informally known as Buddha's birthday, it commemorates the birth, enlightenment and death of the Buddha, Siddhartha Gautama. Buddhist scriptures state that each of these significant events occurred on the full moon of the Indian lunar month of Vesakha. Buddhists celebrate Vesak every year on the day of the full moon in May.

In Indonesia, celebrations were focused on the ancient Borobudur temple. Thousands of Buddhist monks gathered to meditate and circuit the temple in a ritual called "Pradaksina". Borobudur, built between the 8th and 9th century, is the world's largest Buddhist temple and a Unesco World Heritage Site. The temple is situated on a remote hilltop in Central Java surrounded by lush jungle and ringed by volcanoes, one of which – Mount Kelud – is still active.

Vesak Day
Indonesian Buddhists release sky lanterns at Borobudur temple in Magelang, Central Java, Indonesia, during celebrations for Vesak DayUlet Ifanasti/Getty Images
Vesak Buddha birthday
Sky lanterns float over the Borobudur temple in Magelang during Vesak Day celebrationsSuryo Wibowo/AFP
Vesak Buddha birthday
The full moon is seen behind sky lanterns over Borobudur temple in Magelang, Central Java, Indonesia, during celebrations for Vesak DayUlet Ifanasti/Getty Images
Vesak Buddha birthday
Buddhist monks walk past the Borobudur temple in Magelang, IndonesiaUlet Ifanasti/Getty Images
Vesak Buddha birthday
A Buddhist monk prays at the Borobudur temple during celebrations for Vesak DayUlet Ifanasti/Getty Images
Vesak Buddha birthday
An Indonesian Buddhist lights candles at the Borobudur temple during celebrations for Vesak DayUlet Ifanasti/Getty Images
Vesak Buddha birthday
A Buddhist meditates at Borobudur temple in IndonesiaUlet Ifanasti/Getty Images
Vesak Buddha birthday
Buddhist monks take part in rituals at Borobudur temple during celebrations for Vesak DayUlet Ifanasti/Getty Images
Vesak Buddha birthday
Indonesian Buddhist monks walk around the streets to collect alms from followers
Vesak Buddha birthday
Buddhist monks walk past a Premier League mural in Magelang, Central JavaUlet Ifanasti/Getty Images
Vesak Buddha birthday
A Buddhist monk receives alms from a child during a procession in Magelang, IndonesiaUlet Ifanasti/Getty Images
Vesak Buddha birthday
Buddhist monks join a procession from Mendut temple to Borobudur temple in Magelang, Central Java, IndonesiaUlet Ifanasti/Getty Images

The birth of Buddha two-and-a-half millennia ago, in the year 623BC, was also celebrated in other countries with large Buddhist populations, such as Thailand, India and Nepal. IBTimes UK presents photos of celebrations of the important event – also known as Buddha Purnima and Buddha Jayanti.

Vesak Buddha birthday
A monkey sits on an idol of Buddha during celebrations of Vesak Day in Kathmandu, NepalNavesh Chitrakar/Reuters
Vesak Buddha birthday
A woman carries a tray filled with butter lamps in Kathmandu, NepalNavesh Chitrakar/Reuters
Vesak Buddha birthday
Nepalese Buddhists offer prayers at Swayambhunath in KathmanduPrakash Mathema/AFP
Vesak Buddha birthday
A Nepalese Buddhist monk performs rituals after lighting oil lamps in KathmanduPrakash Mathema/AFP
Vesak Buddha birthday
Buddhist priests wearing masks take part in a procession at the Enlightened Heart Tibetan Buddhist temple in Ipoh, MalaysiaManan Vatsyayana/AFP
Vesak Buddha birthday
Buddhist monks pray during a ceremony in Thailand's southern province of NarathiwatMadaree Tohlala/AFP
Vesak Buddha birthday
People pray and light candles at the Marble Temple or Wat Benchamabophit during celebrations of Vesak in Bangkok, ThailandJorge Silva/Reuters