Cambodia rewards a first visit with the temples of Angkor: Angkor Wat at sunrise, the largest religious monument in the world, the stone faces of the Bayon and Ta Prohm wrapped in tree roots. Add a circus night in Siem Reap, a boat on the Tonle Sap lake, and Phnom Penh's Royal Palace, National Museum and riverside, plus the hard history of Tuol Sleng. Siem Reap and Phnom Penh are about 6 hours apart by bus.
This list starts with our ranked picks for a first trip, best first, each with a practical tip on timing and tickets. Below them you will find every sight we cover in Siem Reap and Phnom Penh, with opening notes and checked entry fees where we have them, and then answers to common questions.
The 18 best things to do in Cambodia
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- 1Siem Reap
Watch sunrise over the towers of Angkor Wat
Angkor Wat, built between 1113 and 1150 by King Suryavarman II, is the largest monument at Angkor, covering about 200 hectares with its moats, and its outline sits on Cambodia's flag. First dedicated to Vishnu, it became a Buddhist pilgrimage site by the 16th century. A 200 m sandstone causeway crosses the moat to the west gate, and inside, three raised galleries lead up to five central towers. Unusually, the temple faces west, so its long bas-reliefs are read counterclockwise. The gates open at 5:00 AM, so many visitors come for sunrise, and the site authority suggests 2 to 3 hours here.
Tip: Cover shoulders and knees and take your hat off inside, and note that children under 12 and pregnant visitors can't climb to the top level.
Search tickets and tours on KlookSources: APSARA National Authority (official); Angkor Enterprise (angkorenterprise.gov.kh); Ministry of Foreign Affairs and International Cooperation of Cambodia, Economic Diplomacy (republishing Lonely Planet); Smartraveller (Australian Department of Foreign Affairs and Trade)Angkor Pass, 1 day: $37 · Angkor Pass, 3 days within 7: $62 · Angkor Pass, 7 days within 30: $72 · Angkor Pass neededLast verified
- 2Siem Reap
Find the smiling stone faces of the Bayon
The Bayon stands at the center of Angkor Thom, the state temple that King Jayavarman VII built at the end of the 12th century. Its upper terrace is a crowd of towers carved with calm, smiling faces: 37 still stand of the 49 or 54 first built. The galleries hold two sets of bas-reliefs, full of myth, history and daily life: market stalls, women grilling fish on skewers and a troop of Chinese foot soldiers. Its first name was Chey Kiri, the Triumphant Mountain. Plan 1.5 to 2 hours, between 7:30 AM and 5:30 PM.
Tip: Walk the outer galleries and their scenes of daily life before you climb to the faces on the upper terrace.
Search tickets and tours on KlookSources: APSARA National Authority (official); Angkor Enterprise (angkorenterprise.gov.kh)Angkor Pass needed - 3Siem Reap
Wander the tree-gripped galleries of Ta Prohm
Ta Prohm is the temple where giant spung trees pour their roots over walls and doorways. Jayavarman VII dedicated it in 1186 as Rajavihara, the royal monastery, and installed a statue of Prajnaparamita, the personification of wisdom, whom he identified with his own mother. Its outer wall encloses an area about 1 km by 700 m. The temple was left close to the state it was found in during the 19th century to keep that romantic look, then consolidated to protect the stones and the many visitors. Beyond the roots, look for the Hall of Dancers and finely carved pediments. It is open 7:30 AM to 5:30 PM.
Tip: Allow 1 to 1.5 hours, and most people enter from the west side, although the temple's ritual entrance was to the east.
Search tickets and tours on KlookSources: APSARA National Authority (official); Angkor Enterprise (angkorenterprise.gov.kh)Angkor Pass needed - 4Phnom Penh
Tour the Royal Palace and Silver Pagoda
King Norodom moved Cambodia's capital to Phnom Penh in 1865, and the palace behind its tall yellow walls is still the king's official residence. Visitors come in by the southern gate. The golden-spired Throne Hall holds thrones used only for coronations, and nearby stands the cast-iron Napoleon Pavilion, a gift from Napoleon III. Next door, the Silver Pagoda, also called Wat Preah Keo, was rebuilt in its current form in 1962. Its floor is laid with five tonnes of silver tiles, and inside sits a life-size gold Buddha set with 2,086 diamonds. Guides wait at the southern gate.
Tip: Plan around the midday break, since it opens 8 to 10:30 AM and 2 to 5 PM and closes on many holidays, and cover shoulders and knees.
Search tickets and tours on KlookSources: Ministry of Foreign Affairs and International Cooperation of Cambodia, Economic Diplomacy (republishing The Culture Trip); Phnom Penh Capital Hall (phnompenh.gov.kh)$[fee]; cover shoulders and knees - 5Phnom Penh
Face Cambodia's recent past at Tuol Sleng
Tuol Sleng Genocide Museum is the memorial site of S-21, the Khmer Rouge interrogation and detention center. It was a high school built in 1962; after Phnom Penh was emptied in April 1975, its classrooms became cells and torture rooms. Between 1975 and 1979, 15,000 to 20,000 people were imprisoned here, and Choeung Ek, 15 km west of the city, was one of its execution sites. Today the classrooms, cells and prisoner photographs are preserved, and the museum's aim is to encourage visitors to become messengers of peace. It opens every day, including public holidays, from 8:00 AM to 5:00 PM, and the audio guide comes in 11 languages.
Tip: Bring cash for the entrance booth, cover arms and legs, and note that the museum says its exhibits may not suit children 14 and under.
Search tickets and tours on KlookSources: Tuol Sleng Genocide Museum (official); Tuol Sleng Genocide Museum (official)International adults: $5 · Audio guide: $5 · Pay in cash at the doorLast verified
- 6Siem Reap
Cross the South Gate causeway into Angkor Thom
Angkor Thom, the Great City, was Jayavarman VII's capital from the late 12th century, a walled square of about 900 hectares with the Bayon at its center. Its 8 m laterite walls run for 12 km behind a wide moat, pierced by five gates. The South Gate, on the road between Angkor Wat and the Bayon, is the best preserved and the busiest. Its 23 m tower carries four faces, and the causeway in front is lined with 54 gods and 54 demons hauling on a giant serpent, the Hindu story of the Churning of the Ocean of Milk.
Tip: Climb onto the wall beside the gate and walk a little way along it for the best view back over the causeway.
Search tickets and tours on KlookSources: APSARA National Authority (official); APSARA National Authority (official)Angkor Pass needed - 7Siem Reap
Climb Phnom Bakheng for sunset over Angkor
Phnom Bakheng was the state temple of Yasodharapura, the first city at Angkor, dedicated about 907 on a hill about 60 m high. Its five-tiered pyramid once carried 109 small sanctuaries, a number tied to Hindu cosmology. From the top you look out over the forest to Angkor Wat, about 1.5 km away, and to the Western Baray reservoir. At sunset the light turns Angkor Wat's towers gold, which makes the hill a favorite sunset spot. The temple is open 5:00 AM to 7:00 PM, and a visit takes about an hour.
Tip: Go up well before sunset to find a place to sit, and note that children under 12 and pregnant visitors can't climb the pyramid.
Search tickets and tours on KlookSources: APSARA National Authority (official); Angkor Enterprise (angkorenterprise.gov.kh); APSARA National Authority (official)Angkor Pass needed - 8Siem Reap
See the finest carvings at Banteay Srei
Banteay Srei, about 25 km north-east of the main temples, was dedicated on 22 April 967 and is often called the jewel of Khmer art. Small in scale and built of pink sandstone, it was the only major temple at Angkor founded by a court dignitary rather than a king. Its carvings have no equal in other Khmer temples, and it was the first temple with pediments that tell stories, such as the demon Ravana shaking Mount Kailasa beneath Shiva. Two of its pediments are now in the National Museum in Phnom Penh and the Musee Guimet in Paris. A visit takes about an hour.
Tip: It opens at 7:30 AM, so leave early and pair it with Beng Mealea or other outlying sites for a full day out.
Search tickets and tours on KlookSources: APSARA National Authority (official); Angkor Enterprise (angkorenterprise.gov.kh); Angkor Enterprise (official Angkor ticket office)Angkor Pass needed - 9Phnom Penh
Meet Khmer sculpture at the National Museum
The National Museum of Cambodia holds one of the world's great collections of Khmer art, with sculpture, ceramics and everyday objects from prehistory through the Angkor era and after. The building, designed by George Groslier after temples seen on ancient bas-reliefs, opened during Khmer New Year on 13 April 1920. It closed under the Khmer Rouge and reopened on 13 April 1979. Look for a carved pediment from Banteay Srei among the stone sculpture, and finish in the courtyard. It sits on Street 13 beside the Royal Palace and opens 8:00 AM to 5:00 PM daily, with last tickets at 4:30 PM.
Tip: Hire a guide at the entrance (tours run in Khmer, English, French and Japanese), and save your photos for the courtyard, since the galleries don't allow them.
Search tickets and tours on KlookSources: National Museum of Cambodia; National Museum of Cambodia (official); APSARA National Authority (official)Foreign adults, 18 and over: $10 · Pay at the doorLast verified
- 10Siem Reap
Spend an evening at Phare, the Cambodian Circus
Phare is a one-hour show of circus, theater, music and dance that runs every night at 8:00 PM, all year. The performers are students and graduates of Phare Ponleu Selpak, an arts school in Battambang founded in 1994 by nine young men returning from a refugee camp after the Khmer Rouge years, and ticket money helps fund the school. From 5:30 PM the site fills with Cambodian street food, drinks and a boutique of students' art, and Phare Cafe serves dinner, from fish amok to beef kroeung, in its open-air seating. After the show, you can meet the performers.
Tip: Book ahead if you want a reserved seat in Section A, or arrive early for the open seating in B and C, since some side spots have partly blocked views.
Sources: Phare, The Cambodian CircusSection C, adult: $18 · Section B, adult: $28 · Section A, adult: $38 · Book a seatLast verified
- 11Siem Reap
Explore the overgrown halls of Preah Khan
Preah Khan was built in 1191 by Jayavarman VII on the field where he defeated an invading Cham army, and he dedicated it to his father. Its first name, Jayasri, means holy city of victory. Inscriptions describe a huge institution of 97,840 attendants, including 1,000 dancers and 1,000 teachers, and it may have served as a university for monks and scholars. Like Ta Prohm, it has been left largely unrestored, with trees growing among long, flat galleries around a Buddhist sanctuary. It lies northeast of Angkor Thom; leave the walled city by its north gate.
Tip: It opens at 7:00 AM and stays open until 6:30 PM, so it fits well at either end of a temple day.
Search tickets and tours on KlookSources: APSARA National Authority (official); Angkor Enterprise (angkorenterprise.gov.kh)Angkor Pass needed - 12Siem Reap
Walk the restored temple mountain of Baphuon
Baphuon, just northwest of the Bayon inside Angkor Thom, was built around 1060 by Udayadityavarman II as a temple mountain for Shiva. Its sandy foundation made it unstable, and in the late 15th century a reclining Buddha 9 m tall and 70 m long was built into its west side. Restorers took it apart in the 1960s and numbered 300,000 stones, but the war stopped work and the records were lost. A second team later rebuilt what was called the world's largest three-dimensional jigsaw puzzle, finished in 2011. Reliefs show scenes from the Ramayana, the Mahabharata and the life of Krishna.
Tip: Walk around to the west side to pick out the reclining Buddha in the stonework, and note that children under 12 and pregnant visitors can't climb to the top.
Search tickets and tours on KlookSources: APSARA National Authority (official); Angkor Enterprise (angkorenterprise.gov.kh)Angkor Pass needed - 13Siem Reap
Take a sunset boat on the Tonle Sap from Chong Kneas
The Tonle Sap is a great freshwater lake that swells and shrinks with the seasons, joined to the Mekong by the 120 km Tonle Sap River. Chong Kneas, 11.4 km from Siem Reap, about 25 minutes by tuk-tuk or taxi on Route 63, has the official boat counter for getting out on it. Boats leave from the official counter in Village 6, with small boats for up to 8 people and bigger ones for groups. The light is best late in the day, and the ticket office suggests leaving between 4:30 and 5:15 PM for a sunset cruise.
Tip: Buy your boat ticket at the Chong Kneas counter, since it isn't sold online, and aim to leave between 4:30 and 5:15 PM.
Search tickets and tours on KlookSources: Angkor Enterprise (angkorenterprise.gov.kh); Angkor Enterprise (official Angkor ticket office)Small boat for 1 to 5 people, total: $28 · Boat tickets at the counter onlyLast verified
- 14Phnom Penh
Stroll Sisowath Quay where two rivers meet
Sisowath Quay is Phnom Penh's riverside promenade, facing the point where the Tonle Sap River meets the Mekong. It is the city's easiest walk, busy with street vendors, local life and visitors, and it links several sights: the riverside Royal Palace and the National Museum are its neighbors, and the 1937 Art Deco Central Market is nearby. The Tonle Sap River here is the same 120 km river that links the great lake near Siem Reap with the Mekong, so a sunset walk ties the two cities together.
Tip: Keep your phone and bag on the side away from the road, since snatch thefts from passing motorbikes happen on the riverfront.
Sources: FCC Collection; Phnom Penh Capital Hall (phnompenh.gov.kh); Ministry of Foreign Affairs and International Cooperation of Cambodia, Economic Diplomacy (republishing The Culture Trip); Angkor Enterprise (official Angkor ticket office); Government of Canada; Smartraveller (Australian Department of Foreign Affairs and Trade)Free to visit - 15Siem Reap
Learn the Angkor story at the Angkor National Museum
The Angkor National Museum in Siem Reap tells the story of the Khmer empire in eight galleries, in order: Khmer civilization, religion and beliefs, the great Khmer kings, Angkor Wat, Angkor Thom, stories carved in stone and ancient dress. A separate gallery holds 1,000 Buddha images. Multimedia displays explain the history for visitors with no background at all, which makes it a good primer before the temples. It is on Vithei Preah Sihanouk Avenue, open from 8:30 AM to 6:00 PM from April to September and to 6:30 PM from October to March.
Tip: Rent an audio guide (ten languages) and visit before your first temple day, or in the midday heat.
Search tickets and tours on KlookSources: Angkor National Museum; Angkor National Museum (official)$[fee]; audio guides at the ticket booth - 16Siem Reap
Eat fish amok in Siem Reap's French Quarter
Fish amok is Cambodia's best-known dish: fish marinated in coconut milk and kroeung, a fresh curry paste, then steamed in a banana leaf. FCC Angkor has served it in Siem Reap's French Quarter since 2003, in The Mansion, with French colonial decor, high ceilings, cooling fans and a veranda, alongside other Khmer classics such as beef lok lak and crying tiger. It opens daily from 6:30 AM to 11:00 PM, so it works for breakfast before a temple morning or for dinner, and the garden bar, Scribe, opens at noon.
Tip: Book a table for dinner on the veranda or come for breakfast before a temple morning, since it opens at 6:30 AM.
Sources: FCC Collection; Phare, The Cambodian CircusPay as you go - 17Siem Reap
Watch carvers and silk weavers at Artisans Angkor
Artisans Angkor has spent over 25 years reviving Khmer crafts and has trained nearly a thousand artisans. At its craft centre on Stung Thmey Street, in central Siem Reap, you walk through workshops where artisans carve stone and wood, work silver and lacquer, and weave silk, and some of them also restore Angkorian carvings. Guided tours run daily from 7:30 AM to 6:00 PM. For the full silk story, its silk farm on National Road 6 in Puok shows mulberry trees, silkworms and weaving, a craft that had almost disappeared before its revival in the 1990s.
Tip: Combine the silk farm in Puok, whose tours run daily from 7:30 AM to 5:30 PM, with a morning or afternoon at the temples.
Search tickets and tours on KlookSources: Artisans Angkor (artisansangkor.com); Artisans Angkor (official); Artisans Angkor (official); Artisans Angkor (artisansangkor.com)Guided tours daily - 18Siem Reap
Scramble through the jungle ruins of Beng Mealea
Beng Mealea, the Lotus Pond, is a large, mostly ruined temple about 40 km east of the main Angkor temples, on the old royal road to Preah Khan of Kompong Svay. It is thought to date from the reign of Suryavarman II, who built Angkor Wat, and shares its style. Big trees now grow over and through the walls, and the site is largely uncleared, so exploring means climbing over fallen blocks to find carvings of apsaras and nagas. It needs its own ticket, separate from the Angkor Pass, and pairs well with Banteay Srei or Kbal Spean for a long day out.
Tip: Hire a guide, as the ticket office recommends, since some paths are hard to walk, and plan the trip in daylight.
Search tickets and tours on KlookSources: Angkor Enterprise (official Angkor ticket office); Angkor Enterprise (angkorenterprise.gov.kh); Angkor Enterprise (official Angkor ticket office)
Every sight, city by city
Central Market
Phnom Penh's 1937 Art Deco market hall, one of the capital's best-known landmarks.Entry: Pay as you goIndependence Monument
A monument on its own roundabout south of the Royal Palace, one of the capital's listed landmarks.Entry: Free to visitSearch tours on KlookMalis Phnom Penh
Chef Luu Meng's Cambodian restaurant on Norodom Boulevard, open daily for breakfast, lunch and dinner.Entry: Pay as you goNational Museum of Cambodia
Cambodia's national museum of Khmer art history, beside the Royal Palace on Street 13.Entry: Pay at the doorSearch tickets and tours on KlookRoyal Palace and Silver Pagoda
The King's official residence, with the Throne Hall and the Silver Pagoda's floor of silver tiles.Entry: $[fee]; cover shoulders and kneesSearch tickets and tours on KlookRussian Market
Phsar Toul Tom Poung, a market south of the center listed among the capital's attractions.Entry: Pay as you goSisowath Quay riverside
The riverside promenade along Sisowath Quay, where the Mekong and Tonle Sap rivers meet.Entry: Free to visitTuol Sleng Genocide Museum
The memorial at S-21, the Khmer Rouge regime's interrogation and detention center in Phnom Penh.Entry: Pay in cash at the doorSearch tickets and tours on KlookWat Phnom
A pagoda in Daun Penh, north of the old center, listed among the capital's attractions.Entry: $[fee]Search tickets and tours on KlookAngkor National Museum
Galleries on the Khmer kings, Angkor Wat and Angkor Thom, with a hall of 1,000 Buddha images.Entry: $[fee]; audio guides at the ticket boothSearch tickets and tours on KlookAngkor Thom South Gate
The Tonle Om Gate, the southern gateway into Angkor Thom, the capital of King Jayavarman VII.Entry: Angkor Pass neededSearch tickets and tours on KlookAngkor Wat
Suryavarman II's 12th-century temple, the largest religious monument in the world, set inside a wide moat.Entry: Angkor Pass neededSearch tickets and tours on KlookArtisans Angkor
A craft center in town where you watch artisans at work on sculpture, silk and lacquerware.Entry: Guided tours dailySearch tickets and tours on KlookArtisans Silk Farm, Puok
A working silk farm on National Road 6 that shows the process from mulberry trees and silkworms to the loom.Entry: Guided tours dailySearch tickets and tours on KlookBanteay Srei
A small 10th-century red sandstone temple to Shiva, known for its elaborate wall carvings.Entry: Angkor Pass neededSearch tickets and tours on KlookBaphuon
An 11th-century temple mountain northwest of the Bayon, whose long restoration was finished in 2011.Entry: Angkor Pass neededSearch tickets and tours on KlookBayon
Jayavarman VII's state temple at the heart of Angkor Thom, known for its towers of serene stone faces.Entry: Angkor Pass neededSearch tickets and tours on KlookChong Kneas
A floating village on the Tonle Sap lake, visited by boat from a counter 11.4 km from town.Entry: Boat tickets at the counter onlySearch tickets and tours on KlookFCC Angkor
A French Quarter restaurant open since 2003, serving Khmer dishes such as fish amok and beef lok lak.Entry: Pay as you goMalis Siem Reap
Chef Luu Meng's Cambodian restaurant on Pokambor Avenue by the Siem Reap river, open from 11 AM.Entry: Pay as you goPhare Café
The open-air café and street food stalls at the Phare circus, open from 5:30 PM before the show.Entry: Pay as you goPhare, the Cambodian Circus
A nightly hour-long show of circus, theater, music and dance by Phare Ponleu Selpak students and graduates.Entry: Book a seatPhnom Bakheng
A late 9th-century hilltop temple, popular at sunset for its view toward Angkor Wat.Entry: Angkor Pass neededSearch tickets and tours on KlookPreah Khan
A 12th-century temple Jayavarman VII built for his father, left largely unrestored among the trees.Entry: Angkor Pass neededSearch tickets and tours on KlookPub Street
Siem Reap's central street of restaurants and bars, listed by the Ministry of Tourism among the town's sights.Entry: Pay as you goTa Prohm
A largely unrestored Angkor temple near Preah Khan, where trees and vegetation grow among the ruins.Entry: Angkor Pass neededSearch tickets and tours on KlookQuestions travelers ask
What are the best things to do in Cambodia for a first trip?
Start in Siem Reap with the temples of Angkor: sunrise at Angkor Wat, the stone faces of the Bayon, the tree roots of Ta Prohm and sunset from Phnom Bakheng. Add the carvings of Banteay Srei and an evening at Phare, the Cambodian Circus. Then take the bus to Phnom Penh for the Royal Palace and Silver Pagoda, the National Museum, the Tuol Sleng Genocide Museum and a walk along Sisowath Quay.
Sources: APSARA National Authority (official); APSARA National Authority (official); APSARA National Authority (official); Angkor Enterprise (angkorenterprise.gov.kh); Phare, The Cambodian Circus; Ministry of Foreign Affairs and International Cooperation of Cambodia, Economic Diplomacy (republishing The Culture Trip); Tuol Sleng Genocide Museum (official); Giant Ibis Transport (giantibis.com)How many days do you need in Cambodia?
Angkor passes come in 1, 3 and 7 day versions; the 3-day pass can be used on any three days within a week. The main temples take time: about 2 to 3 hours for Angkor Wat, 1.5 to 2 for the Bayon and 1 to 1.5 for Ta Prohm, so three temple days with Banteay Srei and Beng Mealea fill a 3-day pass at an easy pace. Phnom Penh is about 6 hours away by bus, so add a travel day and at least one full day there.
Sources: Angkor Enterprise (angkorenterprise.gov.kh); APSARA National Authority (official); APSARA National Authority (official); APSARA National Authority (official); Giant Ibis Transport (giantibis.com)What is the best time to visit Cambodia for sightseeing?
The drier, cooler months from November to February are the peak season for Angkor. Rain falls mostly from May to November, with severe storms and flooding most likely from July, and rural roads can be harder going then. The temples stay open all year, and early starts help in any season: Angkor Wat and Phnom Bakheng open at 5:00 AM, and most other temples open by 7:30 AM.
Sources: Ministry of Foreign Affairs and International Cooperation of Cambodia, Economic Diplomacy (republishing Lonely Planet); Smartraveller (Australian Department of Foreign Affairs and Trade); Government of Canada; APSARA National Authority (official); APSARA National Authority (official); APSARA National Authority (official)Which Cambodia attractions should you book ahead?
Buy your Angkor Pass before you go: the official ticket office sells it online in 1, 3 and 7 day versions. Book Phare, the Cambodian Circus ahead if you want a reserved seat in Section A, since the other sections are open seating. Reserve a seat on the bus between Phnom Penh and Siem Reap. You can't prebook the Chong Kneas boats, which are sold only at the counter, and Tuol Sleng and the National Museum sell tickets at their entrance booths.
Sources: Angkor Enterprise (angkorenterprise.gov.kh); Phare, The Cambodian Circus; Giant Ibis Transport (giantibis.com); Angkor Enterprise (angkorenterprise.gov.kh); Ministry of Foreign Affairs and International Cooperation of Cambodia, Economic Diplomacy (republishing The Culture Trip); Tuol Sleng Genocide Museum (official); National Museum of CambodiaHow do you get around Cambodia?
Giant Ibis buses link Phnom Penh and Siem Reap in about 6 hours, with day departures at 8:45 AM, 9:45 AM and 12:30 PM and night buses. Phnom Penh's Techo International Airport is about 20 km south of the city, with taxis and Grab, WowNow or PassApp rides. In both cities, ride-hailing apps such as Grab and PassApp are common and often safer than a flagged-down ride. Around Angkor, go by tuk-tuk, car, bicycle or electric bicycle, and skip renting a motorbike.
Sources: Giant Ibis Transport (giantibis.com); Giant Ibis Transport (giantibis.com); Techo International Airport (techoairport.com.kh); Smartraveller (Australian Department of Foreign Affairs and Trade); Ministry of Foreign Affairs and International Cooperation of Cambodia, Economic Diplomacy (republishing Lonely Planet); Government of CanadaWhat should you wear and what money should you bring in Cambodia?
Cover your shoulders and knees at temples and the Royal Palace, since modesty rules are enforced at sites such as Angkor Wat, and take hats off inside Angkor Wat. Ask before you photograph people, including monks. The riel is the official currency, but US dollars are legal tender and widely used, so carry clean, undamaged notes: torn ones are refused. Cards are not widely accepted outside the main cities, and Tuol Sleng takes cash only.
Sources: Smartraveller (Australian Department of Foreign Affairs and Trade); Government of Canada; APSARA National Authority (official); Ministry of Foreign Affairs and International Cooperation of Cambodia, Economic Diplomacy (republishing The Culture Trip); Tuol Sleng Genocide Museum (official)