On the first day there we stayed in a very nice hotel (Riva Surya) on the Chao Phraya river. The river is the main portion of a river system - it runs about 230 miles and Bangkok is near the end where it runs into the Gulf of Thailand. At Bangkok it is tidal so the height varies as does the direction of flow. There is lots of river traffic - small ferries, freight boats, worker's boats of varying types and decor, and debris - naturaly and man-made.
Our hotel was right next to a ferry dock and we took the ferry down a bunch of stops to the main stop where we caught the BTS sky train (an elevated metro - there are two intersecting lines + a Metro which we never got around to taking) to go to a market.
You can see Wat Arun, an elaborate complex that we didn't get to visit on one side and the Grand Palace, an even more elaborate complex that we visited several days later. In addition to these structures and some fancy hotels there are warehouses and what looks like some pretty rundown housing on the side of the river. One of the bridges is the suspension type like the Leonard Zakim bridge in Boston.
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