I have never seen anything like the floating market. The boats loaded with produce and street food (can you call it that if it's served on a river?) were fun to photograph. And yes, be brave enough to pick up some snacks or lunch from the passing boats. I really wasn't interested in the stalls that sold clothing or souvenirs, but I wish we had stayed longer.
I booked a tour with Best Bangkok Thailand Tour (the concierge recommended them, they had a flashy catalog of tours at the front desk). They were TERRIBLE. It was supposed to be a half-day tour to the Damnoen Saduak floating market. My main beef with them: Instead of focusing on the floating market, we made several other stops that took time away from what would have been the main attraction. In total, we spent less than 30 minutes at the market. I barely had time to get a snack (ripe mango and rice cake -which was delicious by the way), before the guide rounded us up and said it was time to go.
One of the stops was at an elephant camp where you could get a pachyderm ride (that was OK for the kids). But the three other stops were to handicraft stores which sold the usual tourist trinkets and tchotchkes. (Methinks the tour company was paid by the stores to bring the captive tourists in.) We wasted 30-45 minutes at each stop. Time that should have been spent exploring the floating market. When the guide told us that our next stop was at a jewelry store all of us passengers staged a mutiny and said enough - we just wanted to go home.
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