Ubosot, Wihan, Chedi and Prang: How to Read a Thai Temple

Published 19 October 2026 · By the Visit-Thailand editorial team · Editor: Terje Moy

A Thai temple (wat) is a group of buildings, not one: the ubosot is the hall where monks are ordained and is marked by boundary stones, the wihan is the hall that houses the main Buddha image for worshippers, and the chedi or prang is the solid tower that enshrines relics. Once you can spot those three, almost any wat in the country makes sense.

Most visitors walk through their first temples seeing a blur of gold, red roofs and statues. The buildings follow a pattern, though, and the Thai names are easy once you know what each structure is for. The definitions on this page follow the Royal Society of Thailand's dictionary, the official reference for the Thai language. How to dress and behave inside is a separate subject, covered in our temple etiquette guide; this page is about reading the architecture.

Ubosot and wihan: two halls that look alike

The two big halls in a wat often have the same tiered roofs and gilded gables, so the building's shape will not tell you which is which. Their purpose does. The Royal Society defines the ubosot, shortened in speech to bot, as the place where monks gather for acts of the Sangha such as reciting the monastic rules (the Patimokkha) and ordaining new monks. Every functioning monastery needs one.

The wihan, also spelled viharn or vihara, is defined as a place that houses a Buddha image, "paired with the bot". It is where lay people come to pray and make offerings, so in many temples it is the larger and busier of the two. Big temples may have several wihan, including long galleries lined with Buddha images around a courtyard.

The giveaway: sema stones

Look at the ground around the outside of the hall. If you see carved stone markers, often leaf-shaped and set on small pedestals or in little shrines at the corners and the middle of each side, you are looking at the ubosot. The Royal Society describes the sema as the marker that shows the boundary of the ubosot. The boundary defines the consecrated space where monastic acts are valid, which is why the wihan does not have them.

Chedi and prang: the towers that hold relics

The tallest structure in a wat is usually not a building you can enter. The Royal Society defines a chedi as a structure shaped like a haystack with a pointed top, built to enshrine revered objects such as relics of the Buddha. English guidebooks often call it a stupa or a pagoda. Thais walk around it clockwise during candle processions on holy days, and smaller chedi in the grounds often hold the ashes of families who supported the temple.

The prang is the other tower shape: tall, rounded and ribbed, which the dictionary compares to a corn cob. The shape is generally traced to Khmer temple building, and you can see older Khmer towers at Phimai, where the Fine Arts Department's own names for the monuments include Prang Hin Daeng and Prang Brahmathat, as well as a naga bridge. The Royal Society treats a prang-topped chedi as a type of chedi ("chedi yot prang"), so the two words overlap rather than compete. The best-known Bangkok example is the central prang of Wat Arun, described with its visiting details in our guide to Wat Pho and Wat Arun.

Ruined towers are where the shapes are easiest to read, because there is no gold to distract you. The old capitals of Ayutthaya and Sukhothai are full of brick chedi and prang in every state of repair.

Mondop, scripture library, sala and kuti

The smaller buildings tell you how a monastery lives. The mondop is a square building with a pointed roof of many tiers; it typically shelters something special, such as a revered image, a footprint of the Buddha or sacred texts. The ho trai is, in the Royal Society's words, a building for storing the Buddhist scriptures (the Tipitaka). Older ones often stand on high bases or in the middle of a pond, usually explained as protection against termites and damp.

A sala is an open-sided Thai pavilion without walls, used for rest or for a particular task. In a temple you will see several kinds: a small sala where people wait or eat, and the sala kan prian, the hall where monks preach. Funeral chanting also takes place in a sala, which is where you would go if invited to a funeral; our guide to Thai funeral etiquette explains that occasion.

The kuti are the monks' houses, often simple wooden or concrete buildings at the back of the grounds. They are private living space, not part of the visit, and the role of the monks who live there is described in our article on monks in Thai daily life. The little house on a post near the gate is usually a spirit shrine, a separate tradition covered in Thai spirit houses.

Reading a temple roof: chofa, bai raka and hang hong

Thai roofs are layered, with two or three overlapping tiers that step down toward the ends of the hall. The decoration along the gable follows a fixed vocabulary:

• Chofa: the tall, slender finial at the very tip of the gable. The Royal Society describes it as shaped like a garuda, with a big chest, slim neck, small beaked head and a long thin crest. From a distance it looks like a curling horn.
• Bai raka: the row of fin-shaped pieces running down the edges of the gable between the chofa and the lower end, like the spines on a dragon's back.
• Hang hong: the ornament at the lower end of each gable edge, named for the tail of the mythical hong (swan), often shaped as a naga head turned upward.
• Na ban: the triangular gable face itself, usually carved or covered in gilded stucco and glass mosaic, often with a deity or a symbol in the center.

Walk around a hall and compare the gable at each end. The front gable is usually the most richly decorated, which helps you find the main entrance when a hall has doors on several sides.

Naga, yaksha and the other guardians

Many temple stairways have handrails in the form of a long serpent whose body runs down the steps and whose heads rear up at the bottom. This is the naga, which the Royal Society defines as a great crested serpent of legend. In Buddhist stories the naga protects the Buddha, and in the northeast it is also tied to the Mekong, as our page on the naga fireballs at the end of Buddhist Lent describes. Northern temples such as Wat Phra That Doi Suthep have long naga stairways climbing the hill.

Huge figures with fangs and bulging eyes at a gate are yaksha (yak in Thai). The dictionary describes them as a class of non-human beings, large and frightening, and also as attendants of Vessavana, guardian of the north in Buddhist cosmology. At a temple their job is to guard the entrance, which is what the general word for gatekeeper (thawaraban) means. Painted figures of warriors or deities on the door panels play the same role, and stone lions are common at the foot of steps.

Northern temples and central Thai temples look different

You do not need to know the history of every period to see the difference between regions. In the north, many older halls are built of dark teak with low, sweeping roofs that come down close to the ground and gables carved in wood, as at the wooden hall of Wat Phan Tao and the small gilded hall at Wat Phra Singh, both on our walk through Chiang Mai's old-city temples. Chedi in the north are often bell-shaped on high stepped bases, sometimes with elephants or naga on their sides.

In Bangkok and the central plains, halls are typically of whitewashed brick with steeper, multi-tiered roofs, glazed orange and green tiles, and gables covered in gilt and glass. The porcelain-covered prang of Wat Arun is the most famous central example. Modern temples mix and exaggerate the old forms; the all-white Wat Rong Khun in Chiang Rai uses the classical vocabulary of chofa, naga and gables in a completely new way.

We have kept dates and style periods out of this page because the official descriptions vary by temple. If you want the history of a particular wat, start with the information board at the site or the Fine Arts Department, which looks after protected monuments.

A ten-minute way to read any wat

1. From the gate, find the tallest tower: is it a pointed, bell-shaped chedi or a rounded, ribbed prang?
2. Walk around the halls and look for sema stones. That is the ubosot; the other big hall is the wihan.
3. Look up at the gables: find the chofa at the tip, the bai raka along the edges and the hang hong at the ends.
4. Check the stairs and gates for naga rails and yaksha guardians.
5. Look for a building on a high base or in a pond: often the scripture library.
6. Leave the monks' quarters at the back alone, and remove your shoes before entering any hall.

Practicing this at a quiet neighborhood temple is easier than at a famous one, and smaller towns such as Lampang have temples where you may be the only visitor. Our culture section has more on Thai Buddhism and everyday life.

Frequently asked questions

What is the difference between an ubosot and a wihan?

The ubosot (bot) is the hall where monks perform formal acts such as ordination, and it is surrounded by sema boundary stones. The wihan houses a Buddha image for lay worshippers and has no sema. From outside they can look almost identical, so the stones are the easiest way to tell them apart.

What is the difference between a chedi and a prang?

A chedi is a solid tower shaped like a bell or haystack with a pointed top, built to hold relics. A prang is taller and rounded, shaped like a corn cob, a form that came from Khmer architecture. The Royal Society dictionary treats a prang-topped chedi as one type of chedi.

What are the snakes on Thai temple stairs?

They are naga, the great crested serpents of Buddhist and Thai legend. Their bodies form the handrails of stairways and their heads rear up at the bottom step. The naga is a protector of the Buddha and of the temple, which is why it guards the way in.

What are the horn-like points on Thai temple roofs?

The tall finial at the tip of each gable is the chofa, which the Royal Society describes as shaped like a garuda with a long crest. The row of fins along the gable edges is the bai raka, and the hooked ornament at the lower end is the hang hong.

Sources

• Royal Society of Thailand – Thai dictionary (entries for ubosot, wihan, chedi, prang, sema, mondop, chofa, bai raka, hang hong, ho trai, sala, kuti, naga, yaksha) (checked October 2026)
• Tourism Authority of Thailand – End of Lent festivals in Thailand (checked October 2026)
• Fine Arts Department – Phimai Historical Park (monument names) (checked October 2026)