The night the Mekong lights up, from Luang Prabang to Nakhon Phanom

Ok Phansa, the end of Buddhist Lent in Laos and Thailand

Ok Phansa closes the three-month rains retreat, when monks stay in their monasteries to meditate, study, and teach. It falls on the fifteenth day of the waxing moon in the eleventh lunar month: in 2026, Monday, October 26, in both Laos and Thailand^[1][2]. Lent began on July 29 in Laos and July 30 in Thailand^[3][4].

The day starts at the temples, with prayers before dawn and alms for the monks^[2]. It ends at the water's edge. People float small rafts of banana trunk and leaves on the Mekong, loaded with flowers, candles, and incense, as offerings to the Buddha and to the naga, the serpent that guards the river. The gesture is also a way to ask the water spirits for forgiveness and let bad luck drift away with the current^[6][7]. In several towns, these offerings grow into huge illuminated boats.

Nakhon Phanom's illuminated boat procession on the Mekong

On the Thai side, this is the big end-of-Lent event: the Tourism Authority of Thailand lists it among its "Signature Thailand Events"^[8]. The fire boats, or Lai Ruea Fai, are bamboo rafts tens of meters long, covered in paper, fabric, and thousands of lights, shaped as nagas, temples, or Buddhist scenes^[6][10].

In Nakhon Phanom, the festival runs from October 16 to 27, 2026, around the provincial hall and along the Mekong. The big night is the 26th. From 6 p.m., after an opening boat, each of the province's twelve districts launches its boat, one every twenty minutes, competing for a royal trophy. The last one is due around 10:20 p.m.^[8]. In the days before, October 22 to 25, Thai and Lao crews race long boats over a 1.2-kilometer course, billed as the longest in the country^[9].

To watch the boats go by, stand on the riverside promenade along Sunthorn Vijit Road, between the provincial hall and the naga statue. The town's local guide recommends arriving in the afternoon with a mat or a folding chair, and warns that riverside hotels are booked months ahead^[10]. Across the river is Thakhek, in Laos, linked by the Third Friendship Bridge^[6].

Naga fireballs in Nong Khai: where and when to watch

Every Ok Phansa night, thousands of people sit on the Thai bank of the Mekong, downstream from Nong Khai, watching for reddish balls of light that seem to shoot up out of the river, rise, and vanish. Local belief says the naga sends them up to greet the Buddha's return at the end of Lent^[12][14].

Sightings cluster in two districts. In 2025, the province counted 287 fireballs, 237 of them in Rattanawapi and 50 in Phon Phisai; in 2024, it counted 371, including 299 in Rattanawapi. The busiest riverbanks are at Ban Tha Muang and Ban Tan Chum^[12][13][14]. Crowds swing widely: about 140,000 spectators in 2024, about 31,500 in 2025, a 78% drop^[12][13].

In 2026, the province holds the festival from October 22 to 28 in Nong Khai town, October 24 to 26 in Rattanawapi, and October 25 to November 3 in Phon Phisai. The fireballs are expected on the night of the 26th^[11]. People float lamps and banana-leaf rafts, but there is no procession of giant boats as in Nakhon Phanom^[11]. Spectators settle in from the afternoon and watch from nightfall until around 8 p.m., depending on the year^[26].

Naga fireballs: what causes them?

Nobody has proven it. A doctor from Nong Khai suggested gases from decaying matter on the riverbed, methane that would ignite on contact with air. Skeptics counter that methane doesn't ignite on its own without phosphine, which is rare in nature, and that it would burn with a blue-green flame, not as a rising orange ball^[15][16].

The other explanation caused an uproar. In 2002, a documentary on Thai channel iTV showed Lao soldiers firing tracer rounds from their bank while the crowd across the river cheered. It sparked protests in Nong Khai, and the Lao ambassador in Bangkok said he was shocked^[17]. Later, biologist Jessada Denduangboripant of Chulalongkorn University photographed the phenomenon for several years: every light he captured started from the banks or from boats, never from mid-river. He received threats for saying so^[18].

Lao authorities deny it. In 2021, the head of Pak Ngum district, across from Nong Khai province, said no shots were fired in the villages checked on Ok Phansa night^[19]. The debate is still open, and it keeps no one from coming to watch.

Vientiane's boats of light on the Mekong riverfront

Vientiane, across the river from Nong Khai, celebrates Ok Phansa from October 25 to 27, 2026, on the riverbank at Wat Chan. On the morning of the 26th, monks chant from 3 to 4 a.m., then receive alms at 7 a.m. At 7 p.m., a candlelight procession circles the temples and the illuminated boats are launched. Shows and fireworks start at 8 p.m., in Chao Anouvong Park and around the Victory Monument^[2].

Floating offerings may only be released in designated areas along the bank, and taking a boat out to the middle of the river is banned^[2]. Long-boat races for the governor's cup fill all three days. The date of the final hadn't been announced by mid-October; in 2025, it was raced the day after Ok Phansa^[2][20].

Luang Prabang's festival of the boats of light, October 27

Luang Prabang holds its big night a day later. On October 26, people mostly float small offerings of light on the river. Tuesday, October 27, is Boun Lai Heua Fai, the festival of the boats of light^[7][21]. It was the same in 2025: the procession came the day after Ok Phansa^[24].

Neighborhoods and temples build their boats in the weeks before, from bamboo and paper, most often in the shape of a naga^[22][7]. In the evening, they are carried down the main street to Wat Xieng Thong, brought down the temple steps, and launched one by one onto the Mekong^[22][23]. Each family also makes its own little banana-leaf raft and lets it drift off with the year's bad luck^[23]. The start time of the procession hadn't been announced by mid-October.

Ok Phansa on the Mekong: which bank should you pick?

Vientiane, Nong Khai, and Nakhon Phanom all fall on the same night, October 26, so you'll have to choose one. Only Luang Prabang is the next day, which lets you see two festivals, for instance Vientiane on the 26th and Luang Prabang on the 27th. The two cities are linked by train. For the Lao side, see also Laos in October.

For giant boats on the water, go to Nakhon Phanom, which publishes an hour-by-hour program^[8]. For waiting on the riverbank with the crowd, it's Nong Khai. For a procession on foot from the temples to the river, it's Luang Prabang, the next day.

On the Thai side, expect crowds: Friday, October 23, is a public holiday, and many Thais stretch the weekend through the 26th, which is a regular workday^[1][25]. On the 26th, alcohol sales are banned in Thailand, with exceptions such as hotels^[5]. Book your room as early as you can. If you plan to cross the border at night, check the Friendship Bridge closing times first (crossing the Mekong's borders).

Pierre-Marie Coupry

Editor-in-chief of the French travel site Bon Plan Voyage, where he has published since 2012. He checks every practical detail against official sources and proofreads everything before it goes live.

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