Klong Toey postal district stretches over a large bit of East Bankok, from the harbour along the Chao Praya to Kong Tan/Pethburi Rd.
What is often meant by it are the market at the Rama4/Rachada intersection, and a slum area which has enjoyed a reputation as a major drug trafficking center.
I'll guide through a walk, starting with part of the market:
Straight into the maze of narrow passages strewn with an array of goods, here an amulet seller with her goods: