Visit Mae Klong Railway Market (Amphawa)

The easiest way to get to the Mae Klong Railway Market from Bangkok is to take a bus or minivan to Samut Songkhram from the Bangkok South Bus Terminal (Saï Taï Maï) or a passenger van from the Chatuchak Minivan Station opposite from Mo Chit Bus Terminal. The Samut Songkhram bus terminal is less than 10 minutes walk from the railway where the famous market is held. You can also come by train from Wongwian Yai station in Bangkok. From there, you will have to take the train to Mahachai (1 hour - 10 THB) then walk 5 minutes to the pier to cross the river (3 THB) then walk 5 minutes to Ban Laem station to take the train to Mae Klong (1 hour - 10 THB). You will then be on the train which passes in the middle of the market. Be careful to time your schedule carefully because there are only 4 trains to Mae Klong per day. You will find all the details of this journey in train from Bangkok to Mae Klong HERE.
Train timetables at Arrival at Mae Klong are 8:30 a.m. - 11:10 a.m. - 2:30 p.m. and 5:40 p.m. Alternatively, there is a train departure from Mae Klong Station at the start of the market at 6:20 a.m. - 9:00 a.m. - 11:30 a.m. and 3:30 p.m.
Note that the punctuality of trains is not always there in Thailand, if you are thinking of coming to see its arrival in the market, allow some margin.
And to reach the Amphawa floating market which is located 9 km away, you can take the blue songthaew (cars) number 333 in front of 7 Eleven (GPS: 13.407850, 100.000562) right next to the railway market.