Forgot to add that I'll be flying in from Tokyo, so jetlag is less of a problem.

it is very rushed.. i doubt you will feel the bkk vibe, just its bad sides--traffic, etc.

i would drop SR for a later trip.

why Kanchaburi?? its a long trip for a day especially on public transportation as the sites are spread out..

the tribes you see on a one day trip including other activities are not going to be very authentic.. you need multi days

Where are you staying in Siem Reap? I know some places will send a taxi for you at Poipet at a pretty small price. It will also solve the problem of the aggressive taxi drivers. Another option is to fly Bkk Phnom Penh and take the bus that way. I think that bus is about $15.

May will be really hot and muggy (like Japan), but at least it won't be as crowded as in the winter.

It is very rushed. Pause and consider what the most important things are that you want to do/see/experience.

For sure I'd skip Kanchanaburi. Indeed, pause and consider whether to save Chiang Mai for next trip. If you made your trip just Bangkok and Siem Reap, you'd have time to experience both places.

Right now you have two days in Siem Reap; it takes three full days just to see the so-called major temples. Get a copy of Dawn Rooney's book, "Angkor: A Guide to Cambodia's Wondrous Temples" to prepare for your trip. Given the chaos and scams at the border, I'd take lcuy up on her offer of a driver to meet you at the border. You'll still need to navigate the border scams (read all about them at www.talesofasia.com) but at least you would have a reliable taxi waiting for you.

Your Chiang Mai time is unrealistically crammed full. You expect to do a trek, elephants and river rafting all in one day? Oh yes, there are tour companies who will take you to all there in one days, but you'll have no genuine experience of the north. If you really want to see hilltribes in their traditional lifeways, you'll need an overnight trek. If you want to interact with elephants who have been treated well, you'll need to go to the Thai Elephant Conservation Center near Lampang or to the Elephants Nature Park. Your first day you plan both a cooking and meditation class... that kind of schedule is not condusive to meditation.

If it were me - and it isn't - I'd fly to Bangkok, spend 3 or 4 days, go to Siem Reap for a week, then back to Bangkok. (Of course, we spent a week in Siem Reap and would have liked more time.)

What to do besides temples in Siem Reap? www.theplf.org

I agree with Kathie. If you really want to see Angkor Wat, skip Chiang Mai. If you are more interested in Thailand, skip Siem Reap. You will not enjoy yourself if your time is too rushed.

I understand your concern about being alone In a car with a guide. However, if you hire a guide recommended by someone on the forum, chances are they come highly recommended. We had a guide for 3 days in Siem Reap we arranged through the PLF foundation and he was very nice. They might have some female guides. A guide gives you added protection against being harassed. You can also stay at Seven Candles Guesthouse (also run by plf - link above in Kathie's post) in SR very cheaply.

Having done the journey from Poipet to Siem Reap by taxi, I would not recommend it for a woman travelling alone. The journey itself is ok, if a little tedious, but the border crossing is horrendous with everybody, notably the Thai and Cambodian border guards trying to scam you! Some can get a bit aggressive when challenged. The usual thing is to insist that you pay an inflated visa I.e about double or trele the actual rate, put th e wrong dates on your visa so you have problems when departing the country and get another " fine" on departure. A group tour would be a lot easier.

Hotels in SR will send a taxi to collect you from the " bus station" in Poipet the problem is that it is not easy to find he bus station, which is, in fact, a cafe! Adding to our problems was the fact that our driver was two hours late! The bus would have been a lot easier! The whole border crossing is like a Wild West town complete with casinos. For more up to date info, check out www.talesofasia.com

Regarding timing, may is not high season in Cambodia so prices will be lower and there will be fewer tourists around Angkor. It will rain but it will also be greener. Not a bad time at all to visit.

Much as I like Chiang Mai, I think it would be best to leave that for another time. Maybe add the time to Bangkok or spend a couple of days in Phnonm Penh.

Thank you very much for your replies! I realise now that it was way too rushed, and have decided to save Chiang Mai for a future trip of northern Thailand. Revised itinerary:

Day 1 (Mon): arrive in BKK late afternoon
Day 2, 3, 4, 5, 6 (Tues-Sat): Bangkok & surrounds
Day 7 (Sun): bus to Siem Reap
Day 8, 9, 10 (Mon-Wed): Siem Reap (will definitely check out the Ponheary Ly foundation, thanks!)
Day 11 (Thurs): bus to Bangkok
Day 12 (Fri): leave BKK in early morning

Would 5 days in Bangkok be too much? Are there suggestions for good daytrips and/or overnight trips from Bangkok where I can see a slightly different side of the country? I thought about Ayutthaya, but wasn't sure if I may become 'templed out' before Angkor Wat.

I also thought about visiting SR a few days earlier and leaving a few spare days at the end (so that I could extend my stay in SR if needed or return to BKK) - but would SR/the border crossing be way more crowded on a weekend?

Thanks for the tips on the border crossing. I've read Tales of Asia and other articles thoroughly and I'll be expecting all the scams. I think I'll try to take the new run-through bus service, if it's functional by then (http://www.bangkokpost.com/breakingnews/337029/bus-service-to-cambodia-launched). Thanks also for the tip about private guides - I think I'll look out for a female guide, or join a tour, at least for the far-flung temples.

Five days is not too much for Bangkok. My first trip to Thailand was 9 days in Bangkok! I still keep going back because I can't get enough of it.

I would consider moving your Siem Reap trip earlier, so you'll have a few days in Bangkok at the end. It's hard to resist shopping in Bangkok, and it's better to do your shopping at the end so you don't have to drag your purchases to Siem Reap and back.

Ayutthaya is a nice day-trip, but it may feel too repetitive since you are gong to Angkor.

Some people like the day trip to the floating market, but it is too touristy for me. I can always fing plenty to do in Bangkok.

5 days is perfect and will allow you to get a good feel for this amazing city... stay central in a good hotel to maximize your experiences..

consider hiring tong (www.tourwithtong.com) for a trip outside the city one day and a whirlwind city tour another day

I really like your second itinerary a lot better than the first one! Looks like the framework of a pretty enjoyable trip to me. And I second the recommendations for Tong and the Ponheary Ly foundation.

Enjoy, take a lot of pictures, and please post a trip report when you return!

Am going to thailand myself late may for 2 months and planning to go to Siem Reap too, from my research i would train from bangkok not bus. http://www.travelfish.org/feature/71