Question

need advise on route from phnom penh to siam reap and then to ho chi minh. thanks

Location

City: Phnom Penh

Undetermined: [None]

Country: Cambodia

Answers

You can go by road from Phnom Penh to Siem Reap through bus or airplane or boat.
Then Siem Reap to Ho Chi Minh, you need to take an airplane or you need to come back to Phnom Penh and then take bus from Phnom Penh to Ho Chi Minh (approximately 5-6 hours).
Thanks
Because the season is just prior to wet season the boat stops travelling from SReap to PPenh till Aug when more water is in river and lake. If you can get a boat the normal 6 hour trip would take over 10 hours being shallow and more expensive. Normal price around $35US one way. Otherwise by bus, many buslines takes 7 hours with a couple stops along way and varies from $5US to $12US one way. Leave PP or SR in either direction around 7am arrive other end 2pm. Hotel in PPenh for price and close to all is Golden Gate / Street 278 near Independence Monument. In SReap many hotels and guesthouse in town near Old Market, best area to stay - Temple Villa Hotel, Green Village Palace Guesthouse. Google any for prices etc
You can go by bus from PP to Siem Reap. There is also airline between PP and Siem Reap. There may be airline from Siem Reap to HCMC. Otherwise it is by bus back to PP then on to HCMC. You must get a visa at the VN embassy in PP in order to enter VietNam. You can't get it at the border.
To Siem Reap, you can take either by bus and board on HighWay 6 A (4 to 5 hrs) and Tonle Sap Lake aproximately 4 hrs, and from Phnom Penh to Ho Chi Minh by by bus on HighWay 1 (aproximately 3 hrs)
After all the other answer you have already got , you can consider the night bus service covering the route Phnom Phen to Sian Reap and Sian Reap Ho Chi Min City .
Some company have a very confortable service with sleepers .

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