Once a year, beneath the full moon of the twelfth lunar month, northern Thailand exhales — and the dark fills with light.
There is a moment, just before it begins, when everything goes quiet. Thousands of people stand shoulder to shoulder in the warm November dark, each cradling a fragile paper lantern, each waiting on a breath they cannot see. Hands cup the small flames at the lanterns’ mouths. The rice-paper shells swell slowly with heat, tugging gently upward like something alive and impatient to leave. Somewhere a bell sounds, or a chant settles into silence, and then — almost as one — ten thousand hands open.
The lanterns rise.
They lift hesitantly at first, wobbling, finding their balance against the night, and then they climb. Soon the whole sky is moving: a slow, drifting galaxy of soft amber lights, ascending in uneven waves toward the moon. People tip their heads back and stop talking. Children point. Strangers reach for one another’s arms. The lanterns thin into a scatter of warm stars, carrying with them — so the belief goes — the bad luck, the grudges, the griefs of the year just gone. This is khom loi, the floating lantern, and this is Yi Peng, the night Chiang Mai turns its sorrows loose into the air.
Two Festivals, One Glowing Season
It is easy to blur Yi Peng and Loy Krathong into a single spectacle, and most visitors do. In northern Thailand they overlap so completely — same season, same full moon, same spirit of release — that the lanterns in the sky and the little rafts on the water feel like two halves of one prayer. But they are, properly speaking, distinct traditions.
Loy Krathong is the national festival, celebrated across Thailand. Loy means “to float,” and a krathong is a small, decorated vessel — traditionally a slice of banana-tree trunk dressed in folded leaves and flowers — that you set adrift on a river, canal, pond, or any moving water. It is a festival of water, and of letting things flow away from you.
Yi Peng is the northern, Lanna counterpart, most closely associated with Chiang Mai and the old kingdom of which it was the capital. Yi means “two” and peng refers to the full-moon day, so the name marks the full moon of the second month of the old Lanna calendar — which falls in the same lunar window as Loy Krathong. Yi Peng is a festival of fire and air: it is the one that fills the sky with sky lanterns.
Because the two land on the same nights, Chiang Mai gets both at once. The rivers glow with floating candles while the heavens fill with rising lanterns, and for a few evenings the city seems suspended between two mirrored fields of light — one drifting down the Ping River, one drifting up toward the stars.
What People Actually Do
In the days leading up to the full moon, the city transforms. Markets bloom with banana leaves, marigolds, lotus buds, and folded-paper lanterns. Temples — the wat that anchor every Thai neighborhood — drape themselves in hundreds of glowing lanterns and string lights, their golden chedi spires lit up against the night. Households and shopfronts hang the distinctive Lanna lanterns: round, ribbed paper globes and star-shaped frames swaying in the warm air.
On the festival nights, families dress up and head to the water. They carry their krathong down to the riverbank, kneel at the edge, light the incense and the central candle, sometimes whisper a wish or an apology, and gently push the little raft out onto the current. They watch it go. People release sky lanterns from courtyards and open fields. There are processions, beauty pageants, traditional Lanna dance, drumming, fireworks, and the smell of grilled food and incense everywhere. Monks chant; offerings are made at the temples. It is, all at once, a religious observance, a community festival, and an enormous, tender act of communal hope.
The Lanna Kingdom and the Twelfth Moon
To understand Yi Peng, it helps to remember that Chiang Mai is not simply northern Thailand — it is the heart of Lanna, the “kingdom of a million rice fields,” whose founder, King Mangrai, established Chiang Mai as its capital in 1296. For centuries Lanna was its own realm, with its own language, script, architecture, and calendar, only later absorbed into the modern Thai state. The festival carries that distinct heritage in its name, its lanterns, and its rituals.
The timing follows the moon, not the Western calendar. Loy Krathong falls on the night of the full moon of the twelfth month of the traditional Thai lunar calendar; Yi Peng on the full moon of the second month of the older Lanna reckoning — the same full moon, counted differently. In practice this lands in November, and the exact dates shift each year with the lunar cycle. By design it arrives at the close of the rainy season, when the monsoon clouds have cleared, the rivers run high and full, the harvest is in, and the night sky is at last open and dry enough to fill with fire.
The traditions are old, woven from many threads — Brahmanic reverence for the waters, indigenous Lanna custom, and Buddhist practice — and over the centuries they braided together into the festivals celebrated today. As with many living traditions, the precise origins are debated and layered rather than settled, which is part of what gives the festival its deep, sedimented feeling: you are doing something people have done, in some form, for a very long time.
Letting Go, Making Merit, Honoring the Buddha
Beneath the spectacle sits a quiet Buddhist heart, and three intentions run through both festivals.
The first is letting go. To float a krathong, or to send up a lantern, is to release the misfortune, anger, and impurity of the past year — to physically watch your troubles carried away by water or air, and to begin again lighter. There is something profound in the choreography of it: you make the thing with your hands, you hold it, you light it, and then you deliberately let it leave. The festival turns an abstract spiritual idea — non-attachment, the releasing of grievance — into a gesture your body can perform.
The second is making merit (tham bun). In Thai Buddhist life, merit is accrued through generosity, devotion, and good deeds, shaping one’s path in this life and the next. The festival nights are merit-rich: offerings at the temples, gifts to monks, acts of respect and humility. The krathong itself is often understood as an offering and an apology — a gesture of thanks and contrition toward Phra Mae Khongkha, the goddess of water, for the river’s nourishment through the year and for the ways people have used and dirtied it.
The third is paying respect to the Buddha. One tradition holds that the floating lights and rising lanterns honor the Buddha — by some tellings, paying homage to a relic, or sending light toward the heavens as an act of devotion. Whatever the particular telling, the gesture points the same way: upward and outward, away from the self.
You do not have to be Buddhist to feel it. Even visitors with no faith at all tend to fall quiet at the riverbank. The act of making a small beautiful thing and then giving it to the current is its own kind of prayer.
The Making of a Krathong
A krathong is a small marvel of folk craft, and making one is half the meaning.
The traditional base is a cross-section of a banana tree trunk — light, buoyant, biodegradable — though bread, husk, and other natural materials are also used. Around it, makers pin banana leaves folded into intricate pleated petals, building up a lotus-like form. Then come the decorations: marigolds, jasmine, orchids, and folded flowers, arranged in concentric rings. At the center sit the essentials — a candle, three sticks of incense, and often a few coins as an offering. Some people add a lock of hair or a clipped fingernail, a small piece of themselves to send away with the year’s misfortunes.
Every element is symbolic. The round form echoes the lotus, the Buddhist emblem of purity rising from muddy water. The lit candle is reverence and the light of wisdom; the incense, devotion; the flowers, offering and beauty. To watch your own krathong drift out, candle steady, flowers trembling on the dark water, is to watch a tiny illuminated version of your hopes leave your hands.
The lanterns of Yi Peng follow a parallel logic in a different medium. The flying khom loi is a rice-paper shell over a thin bamboo or wire frame, with a fuel cell at the mouth; lit, it fills with hot air and rises like a miniature balloon. The hanging khom fai and the decorative Lanna paper lanterns are not released but strung up to glow at homes and temples. Together they make the city’s light: water below, fire above, paper everywhere.
The Great Releases
The image that draws people from across the world is the mass lantern release — thousands of khom loi ascending in unison, turning the sky into a slow river of light. The most famous of these are large, organized events held on the outskirts of Chiang Mai, often centered on Buddhist ceremony, with mass meditation and chanting preceding the moment when the lanterns go up all at once. These ticketed gatherings have become globally iconic, photographed endlessly, and are frequently what people picture when they imagine the festival.
It is worth being clear-eyed about them. The grand simultaneous releases are largely organized, often commercial events, sometimes scheduled on different nights from the traditional Loy Krathong / Yi Peng dates and held primarily for visitors and photographers. They are genuinely beautiful — but they are a curated, modern expression of the festival, not the whole of it. The older, quieter heart of Yi Peng beats just as strongly in a neighborhood temple courtyard or at a family’s stretch of riverbank.
Beauty and Its Costs
A festival built on releasing fire and flowers into the air and water carries real consequences, and Chiang Mai has spent years reckoning with them.
Air safety is the most acute concern. Thousands of open flames drifting at altitude pose a hazard to aircraft, and during the festival period Chiang Mai’s airport routinely cancels, delays, or reroutes flights, with authorities imposing time windows and no-fly zones for lanterns to protect air traffic. Travelers flying in or out around the festival should expect schedule disruption.
Fire risk is constant. A lantern that fails to clear a rooftop, or lands while still burning, can ignite homes, dry fields, and forest. Every year brings reports of lantern-related fires and damage.
Litter and harm to animals trail the celebration. Spent lanterns fall to earth as a scatter of wire and scorched paper across fields, roads, and waterways; the metal and wire frames can entangle or be eaten by livestock and wildlife. On the water, the sheer volume of krathong — historically often made with non-biodegradable foam (polystyrene) bases and other plastics — has at times choked rivers and canals. City crews haul out enormous quantities of krathong from Bangkok’s and Chiang Mai’s waterways the morning after.
In response, regulations and gentler practices have grown up alongside the festival. Authorities restrict where and when lanterns may be released and coordinate with the airport on no-fly windows. There is a strong push toward biodegradable krathong — banana trunk, leaf, bread, and natural materials over foam and plastic — and toward smaller, shared, or even fully eco-conscious vessels. Some communities and businesses now favor digital or symbolic alternatives, or simply fewer lanterns. None of this fully resolves the tension between a festival of mass release and a finite, shared environment — but the conversation, and the cleanup, have become part of the tradition too.
Tourism and the Authentic Festival
Yi Peng’s fame is a double-edged gift. Global attention has brought income, pride, and preservation; it has also produced staged events, crowding, rising prices, and the familiar friction between a sacred local rite and a bucket-list photo. The most Instagrammed lantern releases can feel, at moments, more like a paid performance than a prayer.
The good news for a thoughtful traveler is that the real festival is everywhere and mostly free. You do not need a ticket to feel it. Walk to the Ping River as the sun goes down. Visit the old temples inside Chiang Mai’s moated square — Wat Phra Singh, Wat Chedi Luang — where lanterns hang in their hundreds and the chanting drifts out into the street. Buy a hand-made krathong from a grandmother at a roadside stall, kneel at the water with the local families, and float it yourself. Be present rather than only behind a lens. Treated as a guest at someone else’s sacred celebration — quiet, respectful, willing to learn the meaning rather than just collect the image — a visitor receives the festival’s true gift, which was never the photograph.
Where and When to Go
The festivals fall on the full moon of the twelfth lunar month, in November, with the exact dates changing each year — so check the lunar calendar before you book, and remember the big organized lantern releases may run on their own separate dates.
Chiang Mai is the place to experience the full convergence of Yi Peng and Loy Krathong: sky lanterns, floating krathong, lantern-draped temples, processions along Tha Phae Road, and the great releases on the city’s edge. Elsewhere in Thailand, Sukhothai — the ancient capital where Loy Krathong’s most romantic origin stories are set — holds celebrations among its illuminated ruins, and Bangkok floats countless krathong on the Chao Phraya River. But for the marriage of fire and water, of Lanna heritage and living devotion, the north is the heart of it.
If you go: book flights and rooms early, expect the airport disruptions around the festival, choose biodegradable krathong, follow the local rules on where lanterns may be released, and step lightly. The festival is generous to those who arrive with humility.
A Lighter Year
In the end, what stays with you is not the scale of it but the gesture. A festival that turns an entire city into an act of release — that takes the heavy, invisible weight of a year and makes it small enough to hold in two hands, light it, and let it rise.
There is a particular stillness in the faces around you as the lanterns climb: a softness, a letting-go that is almost visible. Whatever you came carrying — a loss, a worry, a wish you were afraid to say aloud — you watch it ascend with everyone else’s into that drifting field of amber light, until you can no longer tell which one was yours. And maybe that is the whole point. Your sorrow becomes part of a sky full of other people’s sorrows and hopes, indistinguishable, shared, and rising.
Then the lanterns fade into stars, the candles wobble away downriver, the night settles, and you walk home a little lighter — ready, as the festival intends, to begin the year again.
Power and Pelf 