What you are looking at are the archaeological remains of Ayutthaya, a city once known for trading and hospitality. Now, these ruins are all that remain from it, and due to the awful recent floods in Thailand, this is how the area looks like now. Click it for full size – it’s worth it
I was unable to find the original picture, all I found was this imgur link; if anybody knows where it’s from, please share – I would appreciate it, and so would other readers.