We are looking at arranging a morning trip through the klongs with The Peninsula's recommended agent, BE tours. They have two on offer, one by long tailed boat which stops at Wat Arun and the Royal Barge museum (we want to go to those places anyway, so that fits in nicely). The other goes to the "Unseen Canals of Nonthaburi" with a Chao Praya River Cruise on an express boat (seats 10-30) which stops at the Royal Barge Musueum and for fish feeding at Wat Chalerm Prakiat.

Which should we choose? The latter is a little longer.

Topping...

Frankly, I don't like tours. I'd opt to hire a boat for a half a day rather than book a tour.

CAJ:
Wait till you get to The Peninsula and go out back to the boat ramp. There are boats out there waiting to be hired by the hour. The Peninsula deck hands will hire the boats for you. These are safer as the Peninsula workers take down boat numbers and negotiate the price for you (500 baht per hour). They will take you anywhere you want to go and bring you back at the time you specify. A two hour tour is usually enough time to see the Khlongs and a few other sights on the river. Hope this helps.
Aloha!

don't take the tour...do as suggested above...ask the boat man on the dock to get you a long tail boat for a thornburi klong tour of 2-3 hours, and maybe slightly longer if you stay at wat arun very long...the barges only take 15 minutes as you have to look into the sheds they are kept in and can't go inside...photos are difficult...
i thought the going rate was about 400B per hour...make sure the hotel person tells the boat man exactly what you want to do...you will have had enough after 3 hours...it lots of fun in those powerful boats...

if you bring a map and you could do the same "tour" wat ANN and the barge museam for the princley sum of about $.50 cents (20-30 baht) round trip.. just use the public river taxis.. these two sites are only about a five minute trip...

in all my years on this site and currently living in bangkok.. I must say that wat ann Tour offered by the pen has to be the biggest rip off I've ever seen

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if you want too hire a long tail boat too take you too the UNSEEN nontubur hawaianstrav---- suggestion seems OK... make sure they really are UNseen cuz taxi boat up there only costs about 40 baht round trip...

Agree with the above that hiring your own boat is better, no stopping off for a look at the "crafts markets" that are an inevitable part of any organized tour. You can make your own itinerary. If you can get the boatman to do it, the canals around the Jim Thompson house are interesting, but don't miss Wat Arun and the area around the Royal Barges which also has some interesting areas.

rhkkmk, I have been to the Royal Barges probably 8 times in the last 20 years and have always been allowed in to see the barges in their slips, has there been a change since I was last there about 3 years ago? I know sometimes they are closed if they are getting the barges ready to go out, but that is quite rare, I think the boats only go out on the King's Birthday.