Cambodia has overland border crossings with Thailand: Poipet, Koh Kong, O’Smach, Pailin, and Kamreang district, Vietnam at Moc Bai and Chau Doc and a crossing with Laos at Voeung Kam. Poipet is the closest to Siem Reap, Koh Kong is close to Sihanoukville and the Vietnamese crossing at Moc Bai is the best to Phnom Penh.  

Types of visa: Tourist and Business at the border. Newest border crossings are at Voeung Kam, Laos & Chau Doc, Vietnam. The Vietnamese crossing at Ha Tien is not open. Voeung Kam is now open in both directions. Check with your embassy for travel security. The vaccination & cholera scams still exist from border guards. Remember a vaccination card is not required.

Validity and cost: Visitors arriving by air can obtain a visa for up to 30 days on arrival at Pochentong International Airport, Phnom Penh. One month visa costs US$20, up to 3 months US$40 and more than 3 months US$60 & extensions may be granted by the Immigration Office in Phnom Penh. However first check prices with your Travel agent or the Consulate.

Application to: Consulates (or Consular section of Embassy) in Bangkok, Hanoi, Ho Chi Minh City, Vientiane (Laos), Moscow and Washington, DC. Business visas are obtainable through the Ministry of Foreign Affairs in Phnom Penh or an official invitation. Tourists on package tours will normally have their visas arranged by the tour operator. You can now obtain a 30 day visa at any border check point like Poipet or Koh Kong via land. 1000 baht. 

VISA EXTENSIONS in Cambodia: Immigration in Sihanoukville won't issue extensions but Samudera Market & capitol Tours does. Visa extensions in Phnom Penh go to Office for Foreigners opposite the airport. Thai Embassy in Phnom Penh is on 196 Norodom. Tel (023-363870. Go in the morning before 11am as when we went it was only open in the mornings

Application requirements: (a) 3 completed application forms. (b) 3 passport-size photos. (c) Passport. (d) Fee. (e) Business card, if applying for Business visa. (f) Proof of sufficent funds to cover stay.

Working days required: Minimum 3 days. Once approved it may be collected either at a Cambodian Mission or issued on arrival at Pochentong (Phnom Penh) airport. Visas valid for one month only may also be issued at Pochentong airport without pre-arrangement, although this must be checked before travel.
Aranyapratet on the Thai side & Poipet on the Cambodian side is a cesspit, a seriously desperate place. Also called a cross border market town but is unfortunately crowded with thieves and beggars and worse. It does have 6 casinos but watch out for touts and don't listen to them. They may say they own the bus line or work for them and even put you on the empty bus then ask for 400 baht to Siam Reap and 400 baht for the non existent check points. Only pay the proper driver. It seems to have deteriorated since I was there a year ago. Cost for a 30 day visa is 1000 Thai baht & they will not take $US.
Tips
Park your vehicle in the secure car park beside the crossing, at the bottom end of the market. Its worth the 100 baht to keep the beggars away. Go directly to the immigration point, do not entertain contact with any of the touts, they are a serious pest and difficult to get rid of once they have latched on to you when stamping out, don't forget to ask for a TM card, no forms are put on display as they get stolen and re-sold to unwary travellers. Dont forget two passport pics for entry visa into Cambodia. Re enter Thailand in the usual way & carry baht.
Warning, 
When entering say that you are going gambling, not leaving country immediately, otherwise you pay a gift of 100B. Re enter Thailand in the usual way. Warning, bring a plastic stool to sit on if you cant stand in queues too long like me, also bring an umbrella, drinking water, something to read, go toilet first as it either rains or is stinking hot. I spent an average of an hour each in all 4 queues out in out in, so 4 hours plus depending on traffic. Not pleasant. Don't let your darling enter into conversation with any of the touts cos they want money for looking after her. The market has got some electrical goods at bargain prices, and yah dong herbs are also a buy if you have an outlet, don't get any exotic wildlife, there are 5 police check points on the way back to Khorat.
If travelling back that way there is a scenic restaurant beside the Kruan Lam Nang Rong reservoir beautiful, good food and cheap. There is desperate poverty down on the border as in most border towns. The average police officer earns 800B/month compared with 8000b for a thai. Rice is still the same price however, so you get the picture I am told by some that its not too safe inside Cambodia, Poipet and the surrounding casinos especially at night, only to be expected. You will see lots of beggar children aged 7 or 8 carries babies of 18 months old, pinching them to make them cry so you will give money. If you give to one you will have twenty of them around you in the blink of an eye. I hated every minute of it and was so glad to get back to khorat.

Please follow the links for Travel from Aranyaprathet to Siam Reap to Phnom Penh then out at Koh Kong or Hat Lek back to Thailand.

PART 1: 

Aranyaprathet to Siam Reap & Angkor Wat: April 2002 but although a lot better in 2007 caution prevails everywhere so watch your valuables and watch the touts.

Via overnight train from Chiangmai to Bangkok we took a cab from Hualompong Railway station in Bangkok via the expressway (approx 7min) to Mor Chit Bus Terminal. You can jump off the train at Don Muang or the stop after then catch a cab . Cost is roughly 113 baht including toll 40 baht with of course meter running! Best bet is take a 1st class air con Bus ( Windows 30 & 31) leaving at 8.00am/ 8.20am etc for 164 baht. You can catch a 2nd class bus (window 6) if on a budget. We took the 8.20am bus which takes 4 1/2 hours to Aranyaprathet near the Cambodian border & then a tuk tuk to the border itself 50 baht and walk across. Once existing Thailand you must pay 1000 baht for your entry Tourist visa into Cambodia on the Cambodian side (no US$ accepted) and then you can catch either catch a pickup or Bus to Siam Reap. There are casinos here and lots of touts and beggars. Be careful of touts as they will try to say there company owns the bus and only give money to the driver as there are many scams about. A bus ticket from Khao San Rd costs anywhere from 150 baht to 400 baht for the journey from Bangkok to Siam Reap but from the border about 200 baht up to $US10. The road is crazy and rough and I mean full of potholes to the only stop and township of Sisapon where you can buy a beer,meal or cold water at inflated prices . They are slowly doing this section of road up but after Sisapon to Siam Reap the road is totally insane and our bus travel was traversing everything from potholes to 10 wheelers with the journey taking anywhere from 4-6 hours including a puncture on the way. By the time you reach Siam Reap all you want to do is dive into the shower and eat. Whatever you do don’t sit in the back of a pickup—choose the cab. In Siam Reap there are many Guesthouses to choose from and nice for roughly $US5 with our one doing washing for free. Next day it was off to Angkor Wat and we hired moto taxi ( a kid on a motrbike) for $US6 a day and you buy tickets on the way at a “tollgate”. As we have seen many ruins we only wanted to spend a little time in Siam Reap so we chose to visit the forest temple, Angkor Tom & then Angkor Wat in that order in one day—no problem. Cost for a one day pass was $20 but for 2-3 days $40. You only need to see the “Big 3 temples” unless you are doing your thesis or want to join the many historians and write a further book which are available everywhere (buy in town any souvenirs or books ). Angkor Tom is full of beggars & mine victims with no legs but the ruins are indeed a “wonder of our world” and well worth seeing.

 Siam Reap town is a bit of a dump but there’s a few good curio bazaars & buys and T shirts are cheap at $2. Lots of mortor cycle taxis and each small route costs 500 riel but they will try to get dollars from you $1 to $2 a trip. Guesthouses have a tendancy to try and get you for everything so caution does prevail and if you do not like a guesthouse then just move on as there are many to choose from. Apart from Angkor Wat, there is nothing else to see in Siam Reap. It is also Ok to walk around at night? not like Phnom Penh which is our next stop & its sad to see the poverty and the never ending amount of Hotels being built— shades of rich and poor everywhere in a country which has a long way to go. You can use Thai baht anywhere.

RECOMMENDATIONS: Travel light as clothing is cheap to buy and try to avoid white T shirts etc as you’ll find out the cleaning isn’t that clean when you get your clothes back after sitting in a dusty bus or pickup. You can use baht anywhere in Siam Reap so save your dollars for Phnom Penh. Make sure also when you change baht to US$ notes are not torn, faded or creased as you will find it hard to exchange. Theres many money changers in Siam Reap and watch out changing money in the Guesthouses as they will rip you. It pays to carry Riel for the beggars. If you pay for a bus ticket make sure you get a ticket as the person may be a tout who will run off & you will then pay again. Cambodia is a country of contrasts. The rich are rich and the poor are just that.

FOOD: Cambodian food is bland, tasteless & chillies come out of a ketchup bottle. Outside food stalls are not hygenic nor are the vendors. Thailand is paradise compared to Cambodia. In fact we found the food was terrible and overpriced apart from cheese, tinned tuna and baguettes. Remember Cambodia runs the 2 tier system of one price for them and one for us so avoid places with picture menus. eg we were stung 160 baht for rice with pork pieces and green vegetables & what we saw was not what we got. Nice Aussie mango & Orange juice is only $1 a litre & shop at the gas stations or superettes. Coke is 40c & water Minerva 25 baht, baguettes 500 riel & cheese is cheap (the best in Indo China thanks to the French influence).

CAUTION: Keep your money and Passport on you at all times & do not trust Guesthouses for storage of. If you get robbed and file at the police station you also have to pay to have your case investigated but more about this next month. There are also no Police blocks to Siam Reap from the border as one tout told us we had to pay 400 baht before we leave? They come up with all sorts of things so don’t listen to any touts at the border. There are also no Tourist Police in Cambodia! In 2005 a friend of ours ex Aus Policeman lost his bag snatched out of a moto. He lost everything passport, money etc so you can imagine the headache he had-- lucky they have an Australian embassy.

TRAVELLING: Next time we fly to Siam Reap? Cambodians love the horn on cars and bikes so be prepared for noise. Don’t believe if they say theres only one boat or bus to Phnom Penh (5 companies vie the ferry & many more the bus trip) as Next week we depart for Phnom Penh by Ferry—stage 2 of our adventure or headache?????? The ferries are Ok but buy water and baguettes etc before you leave. Cost to Phnom Penh on the ferry is $20US and your guesthouse can arrange. The trip takes approx 6 hours and its a bumpy ride just to go to the ferry for 1 hour.

MEETING PLACE IN THAILAND: The Cambodian people are really nice and when you get to know them they are very friendly. Many come to Pratunam and buy garments to take home and the ones we met were excellent so not all Cambodia is bad.